classifications of engines, including: internal and external combustion rotary and reciprocating engines spark ignition and compression ignition engines engine cylinder arrangements engine configurations, including: inline engines, vee-type engines and slant cylinder engines opposed cylinder engines camshaft and valve locations, including: overhead cam (OHC) overhead valve (OHV) engine operating principles, including: combustion, including: air-fuel ratios and flame propagation direct and indirect fuel injection detonation and pre-ignition two-stroke and four-stroke cycles engine measurement and performance, including: bore and stroke, including: oversquare and undersquare engines crank throw swept volume and engine volume compression ratio engine efficiency, including volumetric efficiency, thermal efficiency and mechanical efficiency torque and horsepower, including brake horsepower construction and operation of petrol engines, including: basic metallurgy relating to engines identification of metric and imperial threads engine components, including cylinder blocks, cylinders, pistons, cylinder heads, combustion chambers, inlet and exhaust manifolds, spark plugs, connecting rods, crankshafts, piston rings, gudgeon pins, camshafts, cams and flywheels combustion chambers, including: L-head, bath-tub, wedge, trapezoidal, hemispherical and heron-type shapes multiple valve designs construction and operation of diesel engines, including: direct and indirect injection swirl chambers pre-combustion chambers engine diagnosis, including: wet and dry compression tests cylinder leakage tests cylinder power balance tests vacuum tests oil pressure tests sources of fluid leaks exhaust smoke diagnosis engine noise diagnosis, including identifying: common engine noises common abnormal combustion noises |