159-478: A flathead engine , also known as a sidevalve engine or valve-in-block engine , is an internal combustion engine with its poppet valves contained within the engine block , instead of in the cylinder head , as in an overhead valve engine . Flatheads were widely used internationally by automobile manufacturers from the late 1890s until the mid-1960s but were replaced by more efficient overhead valve and overhead camshaft engines . They are currently experiencing
318-806: A 3 ⁄ 4 ‑ton class. Bantam officials met with chiefs of Infantry and Cavalry and suggested a contract to further develop military versions of their light car. But in June 1940—as a collaboration with the Quartermaster Corps (QMC), still responsible for U.S. unarmored tactical military vehicles in 1940—the Ordnance Corps initiated a Technical (sub-)Committee, for the QMC to formulate comprehensive, exact specification for this new, very lightweight, cross-country tactical vehicle, capable of carrying personnel and equipment across rough terrain. The committee included
477-433: A carburetor or fuel injection as port injection or direct injection . Most SI engines have a single spark plug per cylinder but some have 2 . A head gasket prevents the gas from leaking between the cylinder head and the engine block. The opening and closing of the valves is controlled by one or several camshafts and springs—or in some engines—a desmodromic mechanism that uses no springs. The camshaft may press directly
636-409: A deflector head . Pistons are open at the bottom and hollow except for an integral reinforcement structure (the piston web). When an engine is working, the gas pressure in the combustion chamber exerts a force on the piston crown which is transferred through its web to a gudgeon pin . Each piston has rings fitted around its circumference that mostly prevent the gases from leaking into the crankcase or
795-428: A gas engine . Also in 1794, Robert Street patented an internal combustion engine, which was also the first to use liquid fuel , and built an engine around that time. In 1798, John Stevens built the first American internal combustion engine. In 1807, French engineers Nicéphore Niépce (who went on to invent photography ) and Claude Niépce ran a prototype internal combustion engine, using controlled dust explosions,
954-470: A locomotive operated by electricity.) In boating, an internal combustion engine that is installed in the hull is referred to as an engine, but the engines that sit on the transom are referred to as motors. Reciprocating piston engines are by far the most common power source for land and water vehicles , including automobiles , motorcycles , ships and to a lesser extent, locomotives (some are electrical but most use diesel engines ). Rotary engines of
1113-545: A 'jeep' was said by the FTC ... to have been originated by the American Bantam [Co.] of Butler, PA '[with U.S. Army officers] and to have been [conceived and] developed by that company. " Willys appealed this ruling, and after a five-year investigation, in 1948 the FTC again ruled that "Willys was unfairly taking credit for the creation and was thus using unfair methods of competition. The FTC ordered Willys to stop claiming they were
1272-481: A Camp Holabird civilian engineer, who was instructed to disregard the presentation, but changed his mind after seeing it. Brown also stayed at the Bantam plant where both Howie and he worked out specifications with Crist for the proposed vehicle. By the end of June 1940, with American Bantam's consultation, the Quartermaster Corps issued their initial specifications. They specified a part-time four-wheel-drive vehicle, with
1431-508: A T-head four-cylinder in-line motorcycle engine in the 1920s. Internal combustion engine An internal combustion engine ( ICE or IC engine ) is a heat engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber that is an integral part of the working fluid flow circuit. In an internal combustion engine, the expansion of the high- temperature and high- pressure gases produced by combustion applies direct force to some component of
1590-594: A battery and charging system; nevertheless, this system is secondary and is added by manufacturers as a luxury for the ease of starting, turning fuel on and off (which can also be done via a switch or mechanical apparatus), and for running auxiliary electrical components and accessories. Most new engines rely on electrical and electronic engine control units (ECU) that also adjust the combustion process to increase efficiency and reduce emissions. Surfaces in contact and relative motion to other surfaces require lubrication to reduce wear, noise and increase efficiency by reducing
1749-404: A carefully timed high-voltage to the proper cylinder. This spark, via the spark plug, ignites the air-fuel mixture in the engine's cylinders. While gasoline internal combustion engines are much easier to start in cold weather than diesel engines, they can still have cold weather starting problems under extreme conditions. For years, the solution was to park the car in heated areas. In some parts of
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#17328548467141908-499: A common power source for lawnmowers , string trimmers , chain saws , leafblowers , pressure washers , snowmobiles , jet skis , outboard motors , mopeds , and motorcycles . There are several possible ways to classify internal combustion engines. By number of strokes: By type of ignition: By mechanical/thermodynamic cycle (these cycles are infrequently used but are commonly found in hybrid vehicles , along with other vehicles manufactured for fuel efficiency ): The base of
2067-501: A complete redesign by Ford in the form of the 1960-introduced M151 jeep . Its influence, however, was much greater than that—manufacturers around the world began building jeeps and similar designs, either under license or not—at first primarily for military purposes, but later also for the civilian market. Willys turned the MB into the civilian Jeep CJ-2A in 1945, making the world's first mass-produced civilian four-wheel drive. The "Jeep" name
2226-421: A complicated valvetrain allows a compact engine that is cheap to manufacture, since the cylinder head may be little more than a simple metal casting. These advantages explain why side valve engines were used for passenger cars for many years, while OHV designs came to be specified only for high-performance applications such as aircraft , luxury cars , sports cars , and some motorcycles . At top dead centre,
2385-518: A day, and after the Army handed Ford and Willys the blueprints of Bantam's detailed technical drawings—though Bantam proved highly capable and productive during the war, entrusted with manufacturing torpedo -motors and more. However, on 7 April 1942, U.S. patent 2278450 for the WWII jeep, titled "Military vehicle body" had been awarded to the U.S. Army , which had applied for it, listing Colonel Byron Q. Jones as
2544-462: A few other engineers and mechanics had rigged together in the factory, back into drawings. The hand-built prototype was then completed in Butler, Pennsylvania , and basically untested, driven by Crist and Probst, to the Army vehicle test center at Camp Holabird , Maryland. It was delivered at 4.30 pm on 23 September 1940, just half an hour within the deadline. The American Bantam Pilot, initially called
2703-488: A few third party after-market modified four-wheel drive 1 ⁄ 2 ‑ton trucks, mainly Marmon-Herrington derived Fords, had been bought after 1935, for testing, but the prevailing belief amongst military higher-ups and Congress was, that all the extra four-wheel-drive hardware would make any truck lighter than a 1 + 1 ⁄ 2 ‑ton payload model, so much heavier that the weight-gain would cancel out any benefits gained from adding four-wheel drive. But after
2862-452: A hand crank. Larger engines typically power their starting motors and ignition systems using the electrical energy stored in a lead–acid battery . The battery's charged state is maintained by an automotive alternator or (previously) a generator which uses engine power to create electrical energy storage. The battery supplies electrical power for starting when the engine has a starting motor system, and supplies electrical power when
3021-416: A horse) had already won over many civilians," and British and French forces also wanted them. Ford, an isolationist , would not sign a contract with an overseas government, but local dealers sold over 50,000 Fords to European forces, who militarized them locally, most famously into ambulances. When the U.S. entered the war in 1917, Ford sold directly to his country, delivering another 15,000 cars before peace
3180-536: A light cross-country weapons carrier. However, after World War I, the United States had a big public debt , and the military had masses of left-over war vehicles, so vehicle budgets were drastically cut. During the first half of the interwar period , the Roaring Twenties , despite a booming economy, United States non-interventionism and neutrality policies were supported by both elite and popular opinion, to
3339-415: A lot. Royal Page Davidson used patents of Charles Duryea to modify chassis, with machine-guns and armor shield, from 1898. At the same time, the arrival and growing use of automobiles led to various individuals pioneering vehicle trips across the U.S., followed by the first transcontinental trips by convoys of vehicles. After the U.S. Army purchased its first truck in 1907, of 5-ton payload capacity, in
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#17328548467143498-585: A makeshift table. And with its simple piano hinge , it allowed opening the hood all the way to the upright windshield, without even needing a prop-rod, and giving excellent access to the engine, also because of its wide opening. By then, the U.S. armed forces were in such haste, and allies like Britain, France, and USSR wanted to acquire these new "Blitz-Buggies", that after initially considering 1,500 pre-production units in total , all three cars were declared 'acceptable', and orders for 1,500 units per company were given for field testing and export. At this time, it
3657-406: A muddy battlefield trail, control the bike and keep it from stalling, damage, or flipping over; and driver training was both costly in terms of time and money. They had poor off-roading ability and lacked payload capacity. Adding a sidecar provided more stability, but payload and cargo space remained very limited, and having only one powered wheel out of three, still meant the combination got stuck
3816-408: A problem would occur as the compression ratio increased as the fuel was igniting due to the rise in temperature that resulted. Charles Kettering developed a lead additive which allowed higher compression ratios, which was progressively abandoned for automotive use from the 1970s onward, partly due to lead poisoning concerns. The fuel mixture is ignited at different progressions of the piston in
3975-731: A reciprocating internal combustion engine is the engine block , which is typically made of cast iron (due to its good wear resistance and low cost) or aluminum . In the latter case, the cylinder liners are made of cast iron or steel, or a coating such as nikasil or alusil . The engine block contains the cylinders . In engines with more than one cylinder they are usually arranged either in 1 row ( straight engine ) or 2 rows ( boxer engine or V engine ); 3 or 4 rows are occasionally used ( W engine ) in contemporary engines, and other engine configurations are possible and have been used. Single-cylinder engines (or thumpers ) are common for motorcycles and other small engines found in light machinery. On
4134-505: A revival in low-revving aero-engines such as the D-Motor . The valve gear comprises a camshaft sited low in the cylinder block which operates the poppet valves via tappets and short pushrods (or sometimes with no pushrods at all). The flathead system obviates the need for further valvetrain components such as lengthy pushrods, rocker arms, overhead valves or overhead camshafts . The sidevalves are typically adjacent, sited on one side of
4293-422: A separate ICE as an auxiliary power unit . Wankel engines are fitted to many unmanned aerial vehicles . ICEs drive large electric generators that power electrical grids. They are found in the form of combustion turbines with a typical electrical output in the range of some 100 MW. Combined cycle power plants use the high temperature exhaust to boil and superheat water steam to run a steam turbine . Thus,
4452-475: A separate blower avoids many of the shortcomings of crankcase scavenging, at the expense of increased complexity which means a higher cost and an increase in maintenance requirement. An engine of this type uses ports or valves for intake and valves for exhaust, except opposed piston engines , which may also use ports for exhaust. The blower is usually of the Roots-type but other types have been used too. This design
4611-416: A separate crankcase ventilation system. The cylinder head is attached to the engine block by numerous bolts or studs . It has several functions. The cylinder head seals the cylinders on the side opposite to the pistons; it contains short ducts (the ports ) for intake and exhaust and the associated intake valves that open to let the cylinder be filled with fresh air and exhaust valves that open to allow
4770-446: A sidevalve engine are poor gas flow, poor combustion chamber shape, and low compression ratio, all of which result in a low-revving engine with low power output and low efficiency. Because sidevalve engines do not burn the fuel efficiently, they suffer from high hydrocarbon emissions. Sidevalve engines can only be used for engines operating on the Otto principle . The combustion chamber shape
4929-606: A single standardized design, for the United States and the Allied forces in World War II , from 1941 until 1945. This also made it (by its light weight) the world's first mass-produced four-wheel-drive car, built in six-figure numbers. The 1 ⁄ 4 -ton jeep became the primary light, wheeled, multi-role vehicle of the United States military and its allies, with President Eisenhower once calling it "one of three decisive weapons
Flathead engine - Misplaced Pages Continue
5088-404: A standardized truck fleet were still ruled out. "This policy was intended to assure speedy production at the outbreak of war, regardless of the maintenance and spare parts problems that might develop later." The new rules more or less allowed the Army to order in late 1939 the U.S. military's first ever light, quantity-produced 4×4 trucks: the half-ton Dodge G-505 VC-series trucks , delivered in
5247-471: A total of 216 different makes and models of motor vehicles to operate, both foreign and domestic, and no good supply system to keep them running. Various light motor vehicles were tested—at first motorcycles with and without sidecars, and some modified Ford Model Ts . But what was needed was a very light, small, battlefield utility vehicle to replace motorcycles (with or without sidecar)—more user-friendly to control, but just as easy to get in and out of. In
5406-604: A two-speed transfer case, three bucket seats, a fold-down windshield, and blackout and driving lights, of just 1,200 lb (540 kg), with a payload up to 600 lb (270 kg), on a wheelbase no longer than 75 in (1.91 m) (the wheelbase of American Bantam's pickup truck), a maximum (collapsible) height of 36 in (91 cm) (three inches above the Howie-Wiley machine-gun carrier), and an engine and drivetrain, capable of smoothly pulling at speeds ranging from 3–50 miles per hour (4.8–80.5 km/h). Its body design
5565-405: Is a fly-back system, using interruption of electrical primary system current through some type of synchronized interrupter. The interrupter can be either contact points or a power transistor. The problem with this type of ignition is that as RPM increases the availability of electrical energy decreases. This is especially a problem, since the amount of energy needed to ignite a more dense fuel mixture
5724-421: Is also why diesel and HCCI engines are more susceptible to cold-starting issues, although they run just as well in cold weather once started. Light duty diesel engines with indirect injection in automobiles and light trucks employ glowplugs (or other pre-heating: see Cummins ISB#6BT ) that pre-heat the combustion chamber just before starting to reduce no-start conditions in cold weather. Most diesels also have
5883-497: Is commonplace in CI engines, and has been occasionally used in SI engines. CI engines that use a blower typically use uniflow scavenging . In this design the cylinder wall contains several intake ports placed uniformly spaced along the circumference just above the position that the piston crown reaches when at BDC. An exhaust valve or several like that of 4-stroke engines is used. The final part of
6042-738: Is delivered to a working fluid not consisting of, mixed with, or contaminated by combustion products. Working fluids for external combustion engines include air, hot water, pressurized water or even boiler -heated liquid sodium . While there are many stationary applications, most ICEs are used in mobile applications and are the primary power supply for vehicles such as cars , aircraft and boats . ICEs are typically powered by hydrocarbon -based fuels like natural gas , gasoline , diesel fuel , or ethanol . Renewable fuels like biodiesel are used in compression ignition (CI) engines and bioethanol or ETBE (ethyl tert-butyl ether) produced from bioethanol in spark ignition (SI) engines. As early as 1900
6201-529: Is driven downward with power, it first uncovers the exhaust port where the burned fuel is expelled under high pressure and then the intake port where the process has been completed and will keep repeating. Later engines used a type of porting devised by the Deutz company to improve performance. It was called the Schnurle Reverse Flow system. DKW licensed this design for all their motorcycles. Their DKW RT 125
6360-415: Is held in place relative to the engine block by main bearings , which allow it to rotate. Bulkheads in the crankcase form a half of every main bearing; the other half is a detachable cap. In some cases a single main bearing deck is used rather than several smaller caps. A connecting rod is connected to offset sections of the crankshaft (the crankpins ) in one end and to the piston in the other end through
6519-406: Is higher. The result was often a high RPM misfire. Capacitor discharge ignition was developed. It produces a rising voltage that is sent to the spark plug. CD system voltages can reach 60,000 volts. CD ignitions use step-up transformers . The step-up transformer uses energy stored in a capacitance to generate electric spark . With either system, a mechanical or electrical control system provides
Flathead engine - Misplaced Pages Continue
6678-445: Is not possible to dedicate a stroke exclusively for each of them. Starting at TDC the cycle consists of: While a 4-stroke engine uses the piston as a positive displacement pump to accomplish scavenging taking 2 of the 4 strokes, a 2-stroke engine uses the last part of the power stroke and the first part of the compression stroke for combined intake and exhaust. The work required to displace the charge and exhaust gases comes from either
6837-475: Is rendered particularly desirable for military purposes" and describes the purpose as being "a convertible small car body so arranged that a single vehicle may be interchangeably used as a cargo truck, personnel carrier, emergency ambulance, field beds, radio car, trench mortar unit, mobile anti-aircraft machine gun unit, or for other purposes." For centuries, horses were used for reconnaissance, communications, and pulling loads, whenever wars were fought, but after
6996-504: Is the Wärtsilä-Sulzer RTA96-C turbocharged 2-stroke diesel, used in large container ships. It is the most efficient and powerful reciprocating internal combustion engine in the world with a thermal efficiency over 50%. For comparison, the most efficient small four-stroke engines are around 43% thermally-efficient (SAE 900648); size is an advantage for efficiency due to the increase in the ratio of volume to surface area. See
7155-472: Is the result of much research and many tests." Hogan credited both military and civilian engineers, especially those working at the Holabird Quartermaster Depot . Nevertheless, Bantam is credited with inventing the original 1 ⁄ 4 ‑ ton jeep in 1940. However, Willys' advertising and branding during and after the war aimed to make the world recognize Willys as the creator of
7314-510: Is true for V-type flathead engines but less of an issue for inline engines which typically have the intake and exhaust ports on the same side of the engine block.) Although a sidevalve engine can safely operate at high speed, its volumetric efficiency swiftly deteriorates, so that high power outputs are not feasible at speed. High volumetric efficiency was less important for early cars because their engines rarely sustained extended high speeds, but designers seeking higher power outputs had to abandon
7473-430: Is unsuitable for Diesel engines , which require a high compression ratio for ignition to occur. In a sidevalve engine, intake and exhaust gases follow a circuitous route, with low volumetric efficiency, or "poor breathing", not least because the exhaust gases interfere with the incoming charge. Because the exhaust follows a lengthy path to leave the engine, there is a tendency for the engine to overheat . (Note: this
7632-450: The 1 ⁄ 2 ‑ton 4×4 Dodges arrived, two decisions were made: greatly more of these 1 ⁄ 2 ‑ton Dodges were ordered (some 80,000 for the 1941 model year revisions), but also, in June 1940, the Army's tactical trucks payload categories were revised. For the first time, the Army introduced a quarter-ton 4×4 truck chassis class, and just above that, the 1 ⁄ 2 ‑ton chassis were going to be supplanted by
7791-465: The "BRC 40" Production began on 31 March 1941, with a total of 2,605 built up to 6 December — the number ordered was raised because Britain and the USSR already wanted more of them supplied under Lend-Lease . The Bantam BRC-40 was the lightest and most nimble of the three early production models, and the Army lauded its good suspension, brakes, and high fuel economy. However, as the company could not meet
7950-980: The Ford flathead V8 engine and the Ford Sidevalve engine . Cadillac produced V-16 flathead engines for their Series 90 luxury cars from 1938–1940. Packard produced flathead inline 8-cylinder engines until 1954. Also in the British Morris Eight , and Morris Minor series I. After WWII , flathead designs began to be superseded by OHV (overhead valve) designs. Flatheads were no longer common in cars , but they continued in more rudimentary vehicles such as off-road military Jeeps . In US custom car and hot rod circles, restored examples of early Ford flathead V8s are still seen. The simplicity, lightness, compactness and reliability might seem ideal for an aero-engine , but because of their low efficiency, early flathead engines were deemed unsuitable. Two notable exceptions were
8109-700: The Howie-Wiley machine gun carrier , ordered by General Walter Short , then Assistant Commander of the Army's Infantry School at Fort Benning, Georgia, and built by Captain Robert G. Howie and Master Sergeant Melvin C. Wiley. Completed in April 1937, with a driver and a gunner laying prone, operating a .30 caliber machine gun, the vehicle was nicknamed the "belly flopper." In France, the project has already been developed and put into production since 1937. The Laffly V15 can be considered
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#17328548467148268-604: The Pyréolophore , which was granted a patent by Napoleon Bonaparte . This engine powered a boat on the Saône river in France. In the same year, Swiss engineer François Isaac de Rivaz invented a hydrogen-based internal combustion engine and powered the engine by electric spark. In 1808, De Rivaz fitted his invention to a primitive working vehicle – "the world's first internal combustion powered automobile". In 1823, Samuel Brown patented
8427-622: The VW Beetle or the Mini , and it has evolved into the currently produced Jeep Wrangler still largely resembling the original jeep design. By 1940, U.S. policies had caused a stark disadvantage compared to Nazi Germany 's aim, building a standard fleet of Wehrmacht (German armed forces) motor vehicles. From 1933, German industry could only produce Wehrmacht-approved trucks. The U.S. Quartermaster's only significant success for standardization, through late September 1939 Army Regulations on tactical trucks,
8586-604: The Wankel rotary engine . A second class of internal combustion engines use continuous combustion: gas turbines , jet engines and most rocket engines , each of which are internal combustion engines on the same principle as previously described. ( Firearms are also a form of internal combustion engine, though of a type so specialized that they are commonly treated as a separate category, along with weaponry such as mortars and anti-aircraft cannons.) In contrast, in external combustion engines , such as steam or Stirling engines , energy
8745-473: The external links for an in-cylinder combustion video in a 2-stroke, optically accessible motorcycle engine. Dugald Clerk developed the first two-cycle engine in 1879. It used a separate cylinder which functioned as a pump in order to transfer the fuel mixture to the cylinder. In 1899 John Day simplified Clerk's design into the type of 2 cycle engine that is very widely used today. Day cycle engines are crankcase scavenged and port timed. The crankcase and
8904-524: The iconic vehicle of World War II, with an almost mythological reputation of toughness, durability, and versatility." It became the workhorse of the American military, replacing horses, other draft animals , and motorcycles in every role, from messaging and cavalry units to supply trains. In addition, improvised field modifications made the jeep capable of just about any other function soldiers could think of. Military jeeps were adopted by countries all over
9063-717: The two-stroke oil in the air-fuel-oil mixture which is then burned along with the fuel. The valve train may be contained in a compartment flooded with lubricant so that no oil pump is required. Willys MB The Willys MB and the Ford GPW , both formally called the U.S. Army truck, 1 ⁄ 4 ‑ton, 4×4, command reconnaissance , commonly known as the Willys Jeep , Jeep , or jeep , and sometimes referred to by its Standard Army vehicle supply nr. G-503 , were highly successful American off-road capable , light military utility vehicles . Well over 600,000 were built to
9222-598: The "Blitz Buggy." As the War Department deemed American Bantam to not have the production capacity or financial resources to deliver on the scale the Army would need, the other two bidders, Ford and Willys, were encouraged to complete their own pilot models for testing. The contract for the new reconnaissance car would be determined by trials. While Bantam's prototype underwent testing at Camp Holabird from 27 September to 16 October, Ford and Willys' technical representatives were invited and given ample opportunity to observe
9381-458: The 360 different models of vehicles now in the Army ... involve nearly a million items of spare parts which neither the War Department nor any other authority can control." This was bad for logistics in times of war, both in terms of supply chains , as well as hindering troops' mobility by, blocking the ability to repair one vehicle by scavenging parts off another. And the Army could still only get multi-axle drive on "tactical" trucks, "requiring
9540-692: The 75th anniversary of the Bantam jeep, invented and originally manufactured in Butler, Pennsylvania, " therein explicitly resolving that Bantam of Butler, PA, invented the jeep, calling it "one of the most famous vehicles in the world," were the only party to deliver a working prototype of a light four-wheel drive reconnaissance car within the required seven weeks, which withstood 30 days of Army testing at Camp Holabird, then further developed that car, and manufactured 2,675 jeeps, before losing further production contracts to Willys and Ford Motor Company, for fear that Bantam would not be able to ramp up production to 75 jeeps
9699-800: The American Aeronca E-107 opposed twin aero engine of 1930 and the Continental A40 flat four of 1931, which became one of the most popular light aircraft engines of the 1930s. Two modern flatheads are the Belgian D-Motor flat-fours and flat-sixes . These are extremely oversquare and compact aero-engines with direct drive to a propeller. Flathead designs have been used on a number of early pre-war motorcycles, in particular US V-twins such as Harley-Davidson and Indian , some British singles, BMW flat twins and Russian copies thereof. The Cleveland Motorcycle Manufacturing Company produced
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#17328548467149858-542: The American Bantam prototype, known as the Bantam Reconnaissance Car, or BRC Pilot, in just two days, and worked up a cost estimate the next day. Bantam's bid was submitted, complete with blueprints, on the 22 July deadline. American Bantam had purchased the assets of American Austin Car Company from the bankruptcy court and had developed their own line of small cars and engine technology, free of licenses from
10017-617: The Army revised the categories. For the first time, a quarter-ton truck tactical (4×4) chassis class was introduced, at the bottom of the range, and the 1 ⁄ 2 ‑ton chassis was supplanted by a 3 ⁄ 4 ‑ton payload class. By the eve of entering World War II, the United States Department of War had determined it needed a 1 ⁄ 4 ‑ton, cross-country reconnaissance vehicle. Although 1 ⁄ 2 ‑ton 4×4s had outperformed 1 + 1 ⁄ 2 ‑ton 4×4 trucks during testing in 1938,
10176-628: The Army's trials. Exterior changes, mainly mounting flat and square front fenders, instead of the first car's bulbous round ones, identify the BRC (Bantam Reconnaissance Car) Mark IIs, also called the "BRC 60" . Both the Willys "Quad" and the Ford "Pygmy" prototypes were very similar to the Bantam Pilot and were joined in testing by Bantam's Mark II models. The Willys Quad immediately stood out because of its strong engine of 60 gross Hp ( SAE ), which
10335-497: The British Austin Motor Company . As the only small car manufacturer in the United States at the time, their design concept was initially to leverage their commercial off-the-shelf components as much as possible. Bantam adapted front sheetmetal body-stampings from its car line: the cowl, dashboard, and curvy front fenders. However, once Brown returned to Camp Holabird, Crist reviewed their thinking, and realized that
10494-591: The French Jeep. 1,200 of these four-wheeled vehicles were produced before the debacle of 1940. By 1939, the U.S. Army began standardizing its general-purpose truck chassis types by payload rating, initially in five classes from 1 ⁄ 2 to 7 + 1 ⁄ 2 short tons (0.45 to 6.80 t). The Quartermaster Corps saw that the Army needed truck chassis to be standardized in crucial basic functional 'types' (body models), and within "payload capacity" classes. Additionally, some crucial features could not be equipped by
10653-583: The German Army. Moreover, lessons were learned, and a second program to develop a cheap, light, nimble multipurpose off-roader, the Volkswagen Kübelwagen , had already started in 1938. America's military faced a severe catch-up situation, both in time and knowledge. In June 1940, the race was on to produce a lightweight, four-wheel-drive cross-country vehicle for the U.S. Army, capable of carrying equipment and personnel across rough terrain. The idea of
10812-732: The QC to commercial trucks after procurement. Cross-country capabilities, like increased ground clearance and multi-axle drive, had to be designed and built into the trucks from the factory. The Quartermaster Corps Technical Committee concurred, and in June 1939 requested the Chief of Staff's approval, to start standardizing truck chassis and bodies procured for the Army into five payload classes: 1 ⁄ 2 ‑ton, 1 1 ⁄ 2 ‑ton, 2 1 ⁄ 2 ‑ton, 4‑ton, and 7 1 ⁄ 2 ‑ton and all tactical trucks had to have (part-time) all-wheel drive capability. Furthermore, to achieve
10971-455: The U.S. Federal Trade Commission (FTC) opened a case, charging Willys-Overland with misrepresentation in their advertising and news claims, on 6 May 1943. According to the New York Times , the FTC ruled that Willys did not perform the "spectacular achievement" of creating, designing and perfecting the "jeep" together with U.S. Army Quartermaster officers, but that: " The idea of creating
11130-404: The U.S. Army Quartermaster Corps recommended the acquisition of a new kind of military vehicle, "... of light weight and compact size, with a low silhouette and high ground clearance, and possess the ability to carry weapons and men over all sorts of rough terrain." The U.S. Army started looking for a small vehicle suited for reconnaissance and messaging, while at the same time searching for
11289-519: The U.S. an increase in size of both the regular Army and the National Guard. The War Department was also authorized to spend an additional $ 12 million on motor transport. The Army then ordered the U.S. military's first ever production quantity of light , 1 ⁄ 2 ‑ton, 4×4 tactical trucks: going on 5,000 Dodge G-505 VC series , which arrived by the Spring of 1940. Until that point, only
11448-509: The U.S. had during WWII." With some 640,000 units built, the 1 ⁄ 4 ‑ton jeeps constituted a quarter of the total military support motor vehicles that the U.S. produced during the war, and almost two-thirds of the 988,000 light 4WD vehicles produced, when counted together with the Dodge WC series . Large numbers of jeeps were provided to U.S. allies, including the Soviet Union at
11607-733: The US Army during the war, called the vehicle "America's greatest contribution to modern warfare." In 1991, the MB Jeep was designated an "International Historic Mechanical Engineering Landmark" by the American Society of Mechanical Engineers . After WWII, the original jeep continued to serve, in the Korean War and other conflicts, until it was updated in the form of the M38 Willys MC and M38A1 Willys MD (in 1949 and 1952 respectively), and received
11766-615: The Wankel design are used in some automobiles, aircraft and motorcycles. These are collectively known as internal-combustion-engine vehicles (ICEV). Where high power-to-weight ratios are required, internal combustion engines appear in the form of combustion turbines , or sometimes Wankel engines. Powered aircraft typically use an ICE which may be a reciprocating engine. Airplanes can instead use jet engines and helicopters can instead employ turboshafts ; both of which are types of turbines. In addition to providing propulsion, aircraft may employ
11925-489: The associated process. While an engine is in operation, the crankshaft rotates continuously at a nearly constant speed . In a 4-stroke ICE, each piston experiences 2 strokes per crankshaft revolution in the following order. Starting the description at TDC, these are: The defining characteristic of this kind of engine is that each piston completes a cycle every crankshaft revolution. The 4 processes of intake, compression, power and exhaust take place in only 2 strokes so that it
12084-413: The battlefield to this day. But motorcycles also had serious limitations. One could be fast on a decent road, but many roads were still so bad, that the U.S. already had a Good Roads Movement in the late 19th century, as increased usage of bicycles required improving the surfaces of existing wagon and carriage trails. The motorcycles of the era were not ideal; only the best motorcyclists could endure
12243-544: The combustion chamber, thus increasing torque, especially at low rpm. Better mixing of the fuel/air charge improves combustion and helps to prevent knocking. An advance in flathead technology resulted from experimentation in the 1920s by Sir Harry Ricardo , who improved their efficiency after studying the gas-flow characteristics of sidevalve engines. The difficulty in designing a high-compression-ratio flathead means that most tend to be spark-ignition designs, and flathead diesels are virtually unknown. The sidevalve arrangement
12402-619: The combustion gases to escape. The valves are often poppet valves but they can also be rotary valves or sleeve valves . However, 2-stroke crankcase scavenged engines connect the gas ports directly to the cylinder wall without poppet valves; the piston controls their opening and occlusion instead. The cylinder head also holds the spark plug in the case of spark ignition engines and the injector for engines that use direct injection. All CI (compression ignition) engines use fuel injection, usually direct injection but some engines instead use indirect injection . SI (spark ignition) engines can use
12561-516: The competition. And only Bantam provided a proper set of technical drawings. Ford joined later, after being approached directly. Although Willys was the low bidder, Willys was penalized for needing more days to make a prototype, and the dollars penalty per extra day put Willys' price above Bantam's – earning them the contract, as the only company committing to deliver a pilot model in 49 days and 70 more pre-production units in 75 days. American Bantam's chief engineer and plant manager, Harold Crist ,
12720-455: The compressed air and combustion products and slide continuously within it while the engine is in operation. In smaller engines, the pistons are made of aluminum; while in larger applications, they are typically made of cast iron. In performance applications, pistons can also be titanium or forged steel for greater strength. The top surface of the piston is called its crown and is typically flat or concave. Some two-stroke engines use pistons with
12879-432: The compressed charge, four-cycle engine. In 1879, Karl Benz patented a reliable two-stroke gasoline engine. Later, in 1886, Benz began the first commercial production of motor vehicles with an internal combustion engine, in which a three-wheeled, four-cycle engine and chassis formed a single unit. In 1892, Rudolf Diesel developed the first compressed charge, compression ignition engine. In 1926, Robert Goddard launched
13038-410: The corresponding ports. The intake manifold connects to the air filter directly, or to a carburetor when one is present, which is then connected to the air filter . It distributes the air incoming from these devices to the individual cylinders. The exhaust manifold is the first component in the exhaust system . It collects the exhaust gases from the cylinders and drives it to the following component in
13197-400: The crankcase or a separate blower. For scavenging, expulsion of burned gas and entry of fresh mix, two main approaches are described: Loop scavenging, and Uniflow scavenging. SAE news published in the 2010s that 'Loop Scavenging' is better under any circumstance than Uniflow Scavenging. Some SI engines are crankcase scavenged and do not use poppet valves. Instead, the crankcase and the part of
13356-401: The crankcase pressure is slightly below intake pressure, to let it be filled with a new charge; this happens when the piston is moving upwards. When the piston is moving downwards the pressure in the crankcase increases and the reed valve closes promptly, then the charge in the crankcase is compressed. When the piston is moving downwards, it also uncovers the exhaust port and the transfer port and
13515-413: The crankcase to the port in the cylinder to provide for intake and another from the exhaust port to the exhaust pipe. The height of the port in relationship to the length of the cylinder is called the "port timing". On the first upstroke of the engine there would be no fuel inducted into the cylinder as the crankcase was empty. On the downstroke, the piston now compresses the fuel mix, which has lubricated
13674-431: The cylinder below the piston is used as a pump. The intake port is connected to the crankcase through a reed valve or a rotary disk valve driven by the engine. For each cylinder, a transfer port connects in one end to the crankcase and in the other end to the cylinder wall. The exhaust port is connected directly to the cylinder wall. The transfer and exhaust port are opened and closed by the piston. The reed valve opens when
13833-411: The cylinder block has fins protruding away from it to cool the engine by directly transferring heat to the air. The cylinder walls are usually finished by honing to obtain a cross hatch , which is able to retain more oil. A too rough surface would quickly harm the engine by excessive wear on the piston. The pistons are short cylindrical parts which seal one end of the cylinder from the high pressure of
13992-416: The cylinder(s), though some flatheads employ the less common "crossflow" "T-head" variant. In a T-head engine, the exhaust gases leave on the opposite side of the cylinder from the intake valve. The sidevalve engine's combustion chamber is not above the piston (as in an OHV (overhead valve) engine) but to the side, above the valves. The spark plug may be sited over the piston (as in an OHV engine) or above
14151-407: The cylinder. Because there is no obstruction in the cylinder of the fuel to move directly out of the exhaust port prior to the piston rising far enough to close the port, early engines used a high domed piston to slow down the flow of fuel. Later the fuel was "resonated" back into the cylinder using an expansion chamber design. When the piston rose close to TDC, a spark ignited the fuel. As the piston
14310-414: The cylinder. At low rpm, the spark is timed to occur close to the piston achieving top dead center. In order to produce more power, as rpm rises the spark is advanced sooner during piston movement. The spark occurs while the fuel is still being compressed progressively more as rpm rises. The necessary high voltage, typically 10,000 volts, is supplied by an induction coil or transformer. The induction coil
14469-687: The early 1930s, the Infantry Board at Fort Benning had become interested in the British Army 's use of the tiny Austin 7 car in a reconnaissance role, and in 1933 received a car from the American Austin Car Company in Pennsylvania which built them under license. Ever since then, their devout on-the-road salesman and (Washington) lobbyist, ex-military Harry Payne kept approaching many U.S. Army and Defense branches and officers, hoping to sell
14628-480: The early 1930s, the U.S. Army experimented with a bantam weight "midget truck" for scouts and raiders. A 1,050 lb (480 kg), low-slung mini-car with a pick-up body, provided by American Austin Car Company , was shown in a 1933 article in Popular Mechanics magazine. One of the pictures showed that the vehicle was light enough to be man-handled—four soldiers could lift it from the ground entirely. But it
14787-413: The early engines which used Hot Tube ignition. When Bosch developed the magneto it became the primary system for producing electricity to energize a spark plug. Many small engines still use magneto ignition. Small engines are started by hand cranking using a recoil starter or hand crank. Prior to Charles F. Kettering of Delco's development of the automotive starter all gasoline engined automobiles used
14946-453: The efficiency is higher because more energy is extracted from the fuel than what could be extracted by the combustion engine alone. Combined cycle power plants achieve efficiencies in the range of 50–60%. In a smaller scale, stationary engines like gas engines or diesel generators are used for backup or for providing electrical power to areas not connected to an electric grid . Small engines (usually 2‐stroke gasoline/petrol engines) are
15105-577: The end of the war, the whole world saw the horse as hopelessly outclassed." Nevertheless—crucially—using four-wheel drive still remained tied to heavier trucks, of 1 1 ⁄ 2 -ton to 5-ton capacity. All through World War I, there were not any light four-wheel-drive vehicles yet. Immediately after World War I, the further and future use of motor vehicles was considered. In many roles, motorized vehicles had successfully replaced horses and other draft animals , but several roles remained that required better or more specialized vehicles. In 1919 already,
15264-543: The engine is off. The battery also supplies electrical power during rare run conditions where the alternator cannot maintain more than 13.8 volts (for a common 12 V automotive electrical system). As alternator voltage falls below 13.8 volts, the lead-acid storage battery increasingly picks up electrical load. During virtually all running conditions, including normal idle conditions, the alternator supplies primary electrical power. Some systems disable alternator field (rotor) power during wide-open throttle conditions. Disabling
15423-415: The engine. The force is typically applied to pistons ( piston engine ), turbine blades ( gas turbine ), a rotor (Wankel engine) , or a nozzle ( jet engine ). This force moves the component over a distance. This process transforms chemical energy into kinetic energy which is used to propel, move or power whatever the engine is attached to. The first commercially successful internal combustion engine
15582-966: The entire Lincoln Highway , from New York City to the Panama–Pacific World Exhibition in San Francisco, taking four months—for making a film about it. Starting in 1916, the Quartermaster Corps was servicing over 100 "motor trucks," of as many as 27 "varieties"; and in March that year, the U.S. Army decided to form its first two motor companies, to be used immediately in the Pancho Villa Expedition in Mexico, starting 14 March 1916. One company got 27 four-wheel drive, 2‑ton, Jeffery off-road Quad trucks . The other got 27 heavy-duty, 1 1 ⁄ 2 ‑ton, long wheelbase, rear-wheel drive White trucks . The U.S. War Department procured
15741-435: The field reduces alternator pulley mechanical loading to nearly zero, maximizing crankshaft power. In this case, the battery supplies all primary electrical power. Gasoline engines take in a mixture of air and gasoline and compress it by the movement of the piston from bottom dead center to top dead center when the fuel is at maximum compression. The reduction in the size of the swept area of the cylinder and taking into account
15900-626: The first days of September 1939, World War Two had escalated in Europe, with Hitler's invasion of Poland , and the Nazi German forces showed the world a new, highly mobile form of warfare, dubbed ‘ Blitzkrieg ʼ, or lightning war, by a coordinated combination of fast moving tanks and motorized infantry , (self-propelled) artillery , and air support. In response, President Franklin Roosevelt , made an emergency proclamation on September 8, 1939. It authorized
16059-511: The first half of 1940, but these were still not light enough for the jobs that both the Infantry and Ordnance branches required it for. By contrast, Germany had already completed a development program to produce off-road capable "Standardized Military Vehicles" (the Einheits-PKW der Wehrmacht ), from 1933 to 1938, which had already yielded a fleet of tens of thousands of standardized vehicles for
16218-648: The first internal combustion engine to be applied industrially. In 1854, in the UK, the Italian inventors Eugenio Barsanti and Felice Matteucci obtained the certification: "Obtaining Motive Power by the Explosion of Gases". In 1857 the Great Seal Patent Office conceded them patent No.1655 for the invention of an "Improved Apparatus for Obtaining Motive Power from Gases". Barsanti and Matteucci obtained other patents for
16377-589: The first liquid-fueled rocket. In 1939, the Heinkel He 178 became the world's first jet aircraft . At one time, the word engine (via Old French , from Latin ingenium , "ability") meant any piece of machinery —a sense that persists in expressions such as siege engine . A "motor" (from Latin motor , "mover") is any machine that produces mechanical power . Traditionally, electric motors are not referred to as "engines"; however, combustion engines are often referred to as "motors". (An electric engine refers to
16536-544: The first stage, the winning manufacturer(s) were given just seven weeks (49 days), from the moment of awarding the contract, to submit their first fully functional prototype and 75 days for completing 70 test vehicles in total. The Army's Ordnance Technical Committee specifications were equally stringent: the vehicle would be four-wheel drive , have a crew of three, on a wheelbase no longer than 75 in (1.91 m), later stretched to 80 in (2.03 m), and tracks no wider than 47 in (1.19 m). The height with
16695-601: The following conditions: The main advantage of 2-stroke engines of this type is mechanical simplicity and a higher power-to-weight ratio than their 4-stroke counterparts. Despite having twice as many power strokes per cycle, less than twice the power of a comparable 4-stroke engine is attainable in practice. In the US, 2-stroke engines were banned for road vehicles due to the pollution. Off-road only motorcycles are still often 2-stroke but are rarely road legal. However, many thousands of 2-stroke lawn maintenance engines are in use. Using
16854-783: The greatest battlefield mobility." Meanwhile, in Asia and the Pacific, Japan had invaded Manchuria in 1931 and was at war with China from 1937 . Its Imperial Army used a small, 2,425 lb (1,100 kg), three-man crew, four-wheel-drive car for reconnaissance and troop movements, the Kurogane Type 95 , produced in limited numbers from 1936. In 1937 Marmon-Herrington presented five 4×4 Fords, and American Bantam (previously American Austin) once again contributed—delivering three Austin derived roadsters in 1938. The U.S. Army itself had also built an experimental light, low-profile scout and gun mover,
17013-517: The gudgeon pin and thus transfers the force and translates the reciprocating motion of the pistons to the circular motion of the crankshaft. The end of the connecting rod attached to the gudgeon pin is called its small end, and the other end, where it is connected to the crankshaft, the big end. The big end has a detachable half to allow assembly around the crankshaft. It is kept together to the connecting rod by removable bolts. The cylinder head has an intake manifold and an exhaust manifold attached to
17172-494: The half-ton 4×4 trucks—both from Marmon-Herrington Ford, and the 1940 Dodge VC series —still proved too large and heavy, and insufficiently agile off-road. Anxious to have a quarter-ton truck in time for America's entry into World War II, the U.S. Army solicited proposals from domestic automobile manufacturers. Recognizing the need to create standard specifications, the Army formalized its requirements on 11 July 1940, and submitted them to 135 U.S. automotive manufacturers. In
17331-505: The high temperature and pressure created by the engine in its compression process. The compression level that occurs is usually twice or more than a gasoline engine. Diesel engines take in air only, and shortly before peak compression, spray a small quantity of diesel fuel into the cylinder via a fuel injector that allows the fuel to instantly ignite. HCCI type engines take in both air and fuel, but continue to rely on an unaided auto-combustion process, due to higher pressures and temperature. This
17490-416: The higher pressure of the charge in the crankcase makes it enter the cylinder through the transfer port, blowing the exhaust gases. Lubrication is accomplished by adding two-stroke oil to the fuel in small ratios. Petroil refers to the mix of gasoline with the aforesaid oil. This kind of 2-stroke engine has a lower efficiency than comparable 4-strokes engines and releases more polluting exhaust gases for
17649-451: The highest thermal efficiencies among internal combustion engines of any kind. Some diesel–electric locomotive engines operate on the 2-stroke cycle. The most powerful of them have a brake power of around 4.5 MW or 6,000 HP . The EMD SD90MAC class of locomotives are an example of such. The comparable class GE AC6000CW , whose prime mover has almost the same brake power, uses a 4-stroke engine. An example of this type of engine
17808-547: The idea of a small, lightweight reconnaissance car to someone Army or Defense, getting some much-needed government contract business for his company. And Payne kept pushing while American Austin had gone bankrupt and its assets were reincorporated into American Bantam . In 1938, American Bantam again loaned three much-improved cars to the Pennsylvania National Guard for trials during summer maneuvers, which were received as reliable, economical and practical. During
17967-419: The intake manifold is an air sleeve that feeds the intake ports. The intake ports are placed at a horizontal angle to the cylinder wall (I.e: they are in plane of the piston crown) to give a swirl to the incoming charge to improve combustion. The largest reciprocating IC are low speed CI engines of this type; they are used for marine propulsion (see marine diesel engine ) or electric power generation and achieve
18126-429: The inventor of the diesel engine, Rudolf Diesel , was using peanut oil to run his engines. Renewable fuels are commonly blended with fossil fuels. Hydrogen , which is rarely used, can be obtained from either fossil fuels or renewable energy. Various scientists and engineers contributed to the development of internal combustion engines. In 1791, John Barber developed the gas turbine . In 1794 Thomas Mead patented
18285-459: The inventor on the patent, though he had performed no work on the design of the vehicle. Filed on 8 October 1941, stating in the application that "The invention described herein, if patented, may be manufactured and used by or for the Government for governmental purposes without the payment of any royalty thereon," the patent relates to a "small car vehicle body having convertible features whereby it
18444-515: The jeep originated with the infantry, which needed a low-profile, powerful vehicle with four-wheel drive and it was turned over to commercial companies (chiefly Bantam , Willys , and Ford ) to deliver—the development repeatedly being described as a " design by committee ." In fall 1941, Lt. E.P. Hogan of the U.S. Army Quartermaster Corps wrote: "Credit for the original design of the Army's truck 1 ⁄ 4 ‑ton, 4×4, may not be claimed by any single individual or manufacturer. This vehicle
18603-472: The jeep. When Willys first applied to trademark the "Jeep" name in February 1943, Bantam, Ford and other companies objected, because of their contributions to the jeep and the war effort. Although many other companies advertised their patriotic efforts to producing the 1 ⁄ 4 ‑ton jeeps—including Ford, featuring their own GPW jeeps in their ads—nobody took their claims as far as Willys-Overland, and
18762-514: The late summer of 1913, the Army Medical and Quartermaster Corps (QC) took a 3 ⁄ 4 -ton QC field-truck, on a 922 mi (1,484 km) multi-leg experimental trek through Alaska for the state's Road Commission—both to try the truck's bad-road supply and maintenance abilities as well as test the state of several important overland connections in the rough territory. 1915 followed the first successful transcontinental motor convoy , traveling
18921-458: The lowest bid that met requirements and specifications, often different makers. However, saving a small percentage initially, on the procurement, overall proved "penny wise, pound foolish" because it led to problematic diversity of the fleet, requiring too much training of operators and mechanics for maintenance and repairs, and an unmanageably large supply of non-interchangeable spare parts: "The commanding officer at Holabird reported in 1935 that,
19080-485: The most prolific motor-tools in the Allied arsenal. Cavalry , mounted infantry , scouts , and messengers could now be mobilized in combat with much greater speed, agility, and near tireless machines, exactly what was wanted for relaying critical orders, getting munitions to machine guns, and scouting miles ahead of advancing units. The quick and nimble motorcycle, "ridden hard through shot and shell to secure victory," has made itself irreplaceable in specific roles on
19239-483: The needed level of standardization, the Quartermaster General urged trucks should be bought en masse from there on. Acting Chief of Staff, George C. Marshall , approved the procurement policy in the summer of 1939. The Quartermaster Corps also wanted to require the truck industry to use dimensionally interchangeable components, but further standardization measures were not approved until 1940. However, in 1940,
19398-419: The new vehicle would have to be mostly new, rather than simply a modified version of an existing Bantam model. He and others at Bantam immediately set about sourcing the right components: transmission, transfer case, driveshafts and axles. Bantam's own engines made just 22 hp, so a 112 cu in (1.8 L) Continental four-cylinder, making 45 horsepower and 86 lb⋅ft (117 N⋅m) of torque
19557-676: The now major Robert Howie, invited for his expertise, having actually built an ultra-light prototype infantry-support vehicle, officers representing the Quartermaster Corps, and the Army's using arms: Infantry, Cavalry, and the two Coastguard divisions, as well as civilian engineers, mainly from Camp Holabird and Bantam. To begin with, the committee sent an Army delegation including Howie, and Camp Holabird vehicle testing engineers, to Butler, Pennsylvania , to visit American Bantam's factory, being invited to an extensive demonstration there, to evaluate their compact cars and production facilities. Once there, Howie stayed several days, and also Robert Brown,
19716-407: The oil into the combustion chamber. A ventilation system drives the small amount of gas that escapes past the pistons during normal operation (the blow-by gases) out of the crankcase so that it does not accumulate contaminating the oil and creating corrosion. In two-stroke gasoline engines the crankcase is part of the air–fuel path and due to the continuous flow of it, two-stroke engines do not need
19875-402: The outer side of the cylinder, passages that contain cooling fluid are cast into the engine block whereas, in some heavy duty engines, the passages are the types of removable cylinder sleeves which can be replaceable. Water-cooled engines contain passages in the engine block where cooling fluid circulates (the water jacket ). Some small engines are air-cooled, and instead of having a water jacket
20034-457: The part of the cylinder below the exhaust port is used as a pump. The operation of the Day cycle engine begins when the crankshaft is turned so that the piston moves from BDC upward (toward the head) creating a vacuum in the crankcase/cylinder area. The carburetor then feeds the fuel mixture into the crankcase through a reed valve or a rotary disk valve (driven by the engine). There are cast in ducts from
20193-427: The path. The exhaust system of an ICE may also include a catalytic converter and muffler . The final section in the path of the exhaust gases is the tailpipe . The top dead center (TDC) of a piston is the position where it is nearest to the valves; bottom dead center (BDC) is the opposite position where it is furthest from them. A stroke is the movement of a piston from TDC to BDC or vice versa, together with
20352-433: The piston gets very close to the flat portion of the cylinder head above, and the resultant squish turbulence produces excellent fuel/air mixing. A feature of the sidevalve design (particularly beneficial for an aero-engine) is that if a valve should seize in its guide and remain partially open, the piston would not be damaged, and the engine would continue operating safely on its other cylinders. The main disadvantages of
20511-412: The piston in the cylinder and the bearings due to the fuel mix having oil added to it. As the piston moves downward it first uncovers the exhaust, but on the first stroke there is no burnt fuel to exhaust. As the piston moves downward further, it uncovers the intake port which has a duct that runs to the crankcase. Since the fuel mix in the crankcase is under pressure, the mix moves through the duct and into
20670-469: The point of isolationism , and no real budgets were allocated. Then, the Wall Street Crash of 1929 , and the following Great Depression resulted in economic austerity policies lasting until the end of the 1930s, thus curtailing any development of new military vehicles, like a light 4WD car. At the same time, there was a drive for standardization. By the end of World War I, U.S. forces overseas had
20829-409: The power wasting in overcoming friction , or to make the mechanism work at all. Also, the lubricant used can reduce excess heat and provide additional cooling to components. At the very least, an engine requires lubrication in the following parts: In 2-stroke crankcase scavenged engines, the interior of the crankcase, and therefore the crankshaft, connecting rod and bottom of the pistons are sprayed by
20988-513: The previous three U.S. wars, but in the new century, his cavalry forces had to move quicker, with more range and more personnel. He was the first to deploy motorcycles, in the Mexican Border War , predominantly a cavalry campaign over wide regions of the Southwest, where Harley-Davidson motorcycles provided to the Army gave the U.S. the advantage over the horse-mounted Mexicans. The U.S. Army
21147-452: The same invention in France, Belgium and Piedmont between 1857 and 1859. In 1860, Belgian engineer Jean Joseph Etienne Lenoir produced a gas-fired internal combustion engine. In 1864, Nicolaus Otto patented the first atmospheric gas engine. In 1872, American George Brayton invented the first commercial liquid-fueled internal combustion engine. In 1876, Nicolaus Otto began working with Gottlieb Daimler and Wilhelm Maybach , patented
21306-498: The sidevalve. A compromise used by the Willys Jeep , Rover , Land Rover , and Rolls-Royce in the 1950s was the "F-head" (or "intake-over-exhaust" valving), which has one sidevalve and one overhead valve per cylinder. The flathead's elongated combustion chamber is prone to preignition (or "knocking") if compression ratio is increased, but improvements such as laser ignition or microwave enhanced ignition might help prevent knocking. Turbulence grooves may increase swirl inside
21465-448: The soldiers liked very much, in such a lightweight, open-top car. Chief engineer Delmar 'Barney' Roos had been working on Willys' four-cylinder car-engine for years, and with many detail changes had managed to get it to 60 hp from an initial low forties output. The Ford Pygmy on the other hand was held back by its tractor engine, Ford's only four-cylinder engine still made in 1940 – despite serious efforts to make it stronger. Dale Roeder
21624-618: The sole creator of the Jeep." Some 70 years later, in a late 2012 article, the Defense Acquisition Research Journal still called the jeep design "...a product of a massive team effort, including all three manufacturers as well as Army engineers, both military and civilian." Moreover, in 2015, the Pennsylvania General Assembly unanimously adopted a non-controversial House Resolution (382): " ...commemorating
21783-401: The start of the 20th century, motorcycles were the first motor vehicles eagerly adopted by the military, either to replace mounted/ridden cavalry horses , or to motorize infantry . The armies of World War I relied on marching men, horses, and railways for movement but its new technologies introduced motor vehicles: the first tanks , armoured car, and artillery tractors. Motorcycles were
21942-400: The stem of the valve or may act upon a rocker arm , again, either directly or through a pushrod . The crankcase is sealed at the bottom with a sump that collects the falling oil during normal operation to be cycled again. The cavity created between the cylinder block and the sump houses a crankshaft that converts the reciprocating motion of the pistons to rotational motion. The crankshaft
22101-409: The time. Aside from large amounts of 1 1 ⁄ 2 - and 2 1 ⁄ 2 ‑ton trucks, and 25,000 3 ⁄ 4 ‑ton Dodges, some 50,000 1 ⁄ 4 ‑ton jeeps were shipped to help Russia during WWII, against Nazi Germany's total production of just over 50,000 Kübelwagens , the jeep's primary counterpart. Historian Charles K. Hyde wrote: "In many respects, the jeep became
22260-592: The valves; but aircraft designs with two plugs per cylinder may use either or both positions. "Pop-up pistons" may be used with compatible heads to increase compression ratio and improve the combustion chamber's shape to prevent knocking . "Pop-up" pistons are so called because, at top dead centre , they protrude above the top of the cylinder block. The advantages of a sidevalve engine include: simplicity, reliability, low part count, low cost, low weight, compactness, responsive low-speed power, low mechanical engine noise, and insensitivity to low-octane fuel. The absence of
22419-617: The vehicle and study its performance. To expedite Ford and Willys' prototypes, the War Department forwarded the Bantam's blueprints to them, claiming the government owned all designs in the proposals submitted to it in the bidding contest. American Bantam chose not to dispute this. Bantam continued building the further 70 prototypes, as per the initial contract. Bantam's original no.01 first remained at Holabird for incessant shake-down and breaking point testing, and ad-hoc fixes and improvements of weaknesses, while by November 1940, Ford and Willys also submitted their first prototypes to compete in
22578-738: The vehicles as rolling chassis , which the manufacturers had to expedite to El Paso, Texas . The wagon bodies for the chassis came from the Quartermaster Depot. The most suitable truck capacity found by the Quartermaster General for Army use to be 1 1 ⁄ 2 ‑ton, matching both the country roads nature, the strength of bridges, as well as the existing troop supply system, at the time also using standard 1 1 ⁄ 2 ‑ton, four-mule wagons. Meanwhile, World War I had been raging in Europe since 1914. More than five years before, Henry Ford had launched his Model T . "... Its speed, durability, stamina, and ease of maintenance (compared to
22737-423: The volume of the combustion chamber is described by a ratio. Early engines had compression ratios of 6 to 1. As compression ratios were increased, the efficiency of the engine increased as well. With early induction and ignition systems the compression ratios had to be kept low. With advances in fuel technology and combustion management, high-performance engines can run reliably at 12:1 ratio. With low octane fuel,
22896-510: The windshield folded down was also raised, to 40 in (1.02 m). The diminutive dimensions were similar in size and weight to American Bantam's compact truck and roadster models. It was now to carry a 660 lb (300 kg) payload and be powered by an engine capable of 85 lb⋅ft (115 N⋅m) of torque. The most daunting demand, however, was an empty weight of no more than 1,275–1,300 lb (580–590 kg). Initially, only American Bantam Car Company and Willys-Overland entered
23055-636: The world, so much so that they became the most widely used and recognizable military vehicle in history. Dwight D. Eisenhower , the Supreme Commander of the Allied Expeditionary Force in Europe in World War II, wrote in his memoirs that most senior officers regarded it as one of the five pieces of equipment most vital to success in Africa and Europe. General George Marshall , Chief of Staff of
23214-549: The world, the oil was actually drained and heated overnight and returned to the engine for cold starts. In the early 1950s, the gasoline Gasifier unit was developed, where, on cold weather starts, raw gasoline was diverted to the unit where part of the fuel was burned causing the other part to become a hot vapor sent directly to the intake valve manifold. This unit was quite popular until electric engine block heaters became standard on gasoline engines sold in cold climates. For ignition, diesel, PPC and HCCI engines rely solely on
23373-499: Was Ford's team leader behind the Pygmy, and his team managed to tune the motor from 30bhp to the specified 40bhp, by using a different camshaft and a bigger carburettor. More importantly, the Ford's front sheetmetal design was the cleverest, fusing all the front lighting behind a straight grille grate, side by side, into one cheap, integrated whole, under a wide, flat, and horizontal hood, useful as
23532-506: Was acknowledged the original weight limit (which even Bantam's Mk.II could not meet) was unrealistic, and it was raised to 2,160 lb (980 kg). On 22 January 1941, the Quartermaster Corps Technical Committee advised standardization of the jeeps across all manufacturers. For the ensuing pre-production runs, each maker's vehicles received further revisions, and new names once more. For 1941, Bantam's got called
23691-464: Was an experienced automobile engineer who had early-on worked on the first Duesenberg and been an engineer at Stutz Motor Company of Indianapolis for 18 years, worked a spell for Marmon , and then for Bantam from 1937 to 1942, drafted freelance Detroit designer Karl Probst to collaborate. Probst initially turned Bantam down, but agreed to work without pay after an Army request and began work on 17 July 1940. Probst laid out full design drawings for
23850-406: Was created by Étienne Lenoir around 1860, and the first modern internal combustion engine, known as the Otto engine , was created in 1876 by Nicolaus Otto . The term internal combustion engine usually refers to an engine in which combustion is intermittent , such as the more familiar two-stroke and four-stroke piston engines, along with variants, such as the six-stroke piston engine and
24009-468: Was especially common in the United States and used for motor vehicle engines, even for engines with high specific power output. Sidevalve designs are still common for many small single-cylinder or twin-cylinder engines, such as lawnmowers , rotavators , two-wheel tractors and other basic farm machinery . Multicylinder flathead engines were used for cars such as the Ford Model T and Ford Model A ,
24168-405: Was one of the first motor vehicles to achieve over 100 mpg as a result. Internal combustion engines require ignition of the mixture, either by spark ignition (SI) or compression ignition (CI) . Before the invention of reliable electrical methods, hot tube and flame methods were used. Experimental engines with laser ignition have been built. The spark-ignition engine was a refinement of
24327-547: Was selected, mated to a Warner Gear transmission. Custom-built four-wheel drive-train components included the Spicer transfer case to send power to the front and rear axles. They were both Spicer-made, originally Studebaker Champion rear axles, but modified for four-wheel drive use. Using off-the-shelf automotive parts where possible had helped to design the car and draw up its blueprints quickly. By working backwards, Probst and American Bantam's draftsmen converted what Crist and
24486-623: Was signed. Britain, France, and Russia were already buying American-made four-wheel-drive trucks from the Four Wheel Drive Auto Company , and Jeffery/Nash Quads , because on the muddy roads and European battlefields, they would not get stuck all the time. The United States procured thousands of motor vehicles for its military, including some 12,800 Dodges, plus thousands of four-wheel-drive trucks: 1 1 ⁄ 2 ‑ton Nash Quads, and 3- and 5-ton FWD trucks. General John J. Pershing viewed horses and mules as acceptable for
24645-442: Was so pleased with further innovations, like a sidecar as a platform to mount machine-guns, that the U.S. procured many more motorcycles than 4WD trucks for World War I. "Entire infantry units were mobilized on motorcycles, and they also provided an ideal way to rapidly deploy machine gun crews into position. Medical units used them to evacuate wounded on stretcher-equipped sidecars, and to return medical supplies and ammunition." "By
24804-401: Was still only rear-wheel drive. After 1935, when the U.S. Congress declared World War I vehicles obsolete, procurement for "remotorization of the Army" gained more traction, but pre-war, peacetime budget restrictions still meant that the U.S. Comptroller General imposed open bidding on every additional, or even incremental procurement. Each time, the Army was forced to award the contract to
24963-412: Was that the War Department limited procurement to just five payload chassis types (categories), from 1 ⁄ 2 ‑ton to 7 + 1 ⁄ 2 ‑ton —but only "models produced commercially by two or more competing companies..." The Army was still to use "commercially standard" trucks and parts, with only minor modifications, like brush-guards, tow-hooks, etc. Specially designed vehicles or
25122-471: Was to be rectangular in shape, including a sketch drawing, handed to the Ordnance Technical Committee. By now the war was underway in Europe, so the Army's need was urgent, but also very demanding. No sooner than July 1940, some 135 manufacturers of automotive or similar equipment were approached by a government letter to submit bids, to be received by 22 July, a span of just eleven days. In
25281-572: Was trademarked, and grew into a successful, and highly valued brand. The success of the jeep inspired both an entire category of recreational 4WDs and SUVs , making "four-wheel drive" a household term, and numerous incarnations of military light utility vehicles . In 2010, the American Enterprise Institute called the jeep "one of the most influential designs in automotive history." Its "sardine tin on wheels" silhouette and slotted grille are perhaps even more instantly recognizable than
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