OHV engine

General description

~1min read

The engine is of four-cylinder. in-line overhead valve type, mounted transversely at the front of the car.

The crankshaft is supported in three shell type main bearings. Thrustwashers are incorporated in the centre main bearing to control crankshaft endfloat.

The connecting rods are attached to the crankshaft by horizontally split shell type big-end bearings. and to the pistons by gudgeon pins which are an interference fit in the connecting rod small-end bore. The aluminium alloy pistons are of the slipper type and are fitted with three piston rings: two compression rings and an oil control ring.

The camshaft is chain driven from the crankshaft and operates the rocker arms via tappets and short pushrods. The inlet and exhaust valves are each closed by a single valve spring and operates in guides, integral with the cylinder head. The valves are actuated directly by the rocker arms.

Engine lubrication is by a gear type oil pump. The pump is mounted beneath the crankcase and is driven by a camshaft, as are the distributor and fuel pump.

Many of the engine component retaining bolts are of the socket-headed type and require the use of Torx type multi-tooth keys or socket bits for removal. These are readily available from retail outlets and should be obtained if major dismantling or repair work is to be carried out on the engine.

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