Manufacturer Motorenwerke Mannheim Configuration Straight-2 Diesel Cylinder bore 98 mm | Production 1955–1960 Displacement 1,8 l (1810 cm³) Piston stroke 120 mm | |
 | ||
The MWM AKD 112 Z is an air-cooled two-cylinder inline diesel engine produced by MWM from 1955 – 1960. One, three and four cylinder variants of the same engine family were also produced by MWM.
Description
The AKD 112 Z is an air-cooled two cylinder four stroke inline diesel engine with overhead valves. The letter Z means Zweizylinder, German for two cylinders.
The crankcase is a single cast piece, the drop-forged crankshaft with counter weights screwed on is supported in bearings made of steel-lead-bronze. The crank and shaft pins of the crankshaft are heat-hardened. Due to the air-cooling of the engine, the cylinders have cooling fins made of centrifugal cast metal. The combustion chamber of the engine is a part of the piston bowls because of the direct injection. The pistons are made of a special highly heat resistant light metal alloy, they have three piston rings and one oil control ring. The connecting rods are cranked as well as the lower crank ends. The lower big crank ends are made of steel-lead-bronze, the upper small crank ends are made of special-bronze. The camshaft is supported by rolling bearings. The overhead valves are pushed by rockers and pushrods. The cylinder head is a single piece made of low pressure chill cast highly heat resistant light metal alloy. The air filter of the engine is a wet filter. For dusty environments MWM offered an oil bath air filter. The air intake must not draw in hot air; this would reduce the engine power output. The fuel is pumped by a Bosch pump. The fuel pump is controlled by a centrifugal control mechanism using a pushrod. The control trap makes it possible to change the injection time at the engine start-up to pump more fuel into the cylinder. A forced feed lubrication system lubricates the engine, powered by a gear oil pump. The oil is filtered by a strainer in the low pressure circuit and a fine sieve strainer in the high pressure circuit. A gap filter in the high pressure circuit was also available. The cooling is done by an axial cooling fan powered by the crankshaft using a belt. The power can be taken off the flywheel or the PTO-shaft. An electric motor can be used to start the engine as well as a crank. The AKD 112 Z does not have glow plugs but a decompression system.