It is a wet sump system - the whole of the oil supply being carried in the oil sump below the crankcase. A gear type oil pump driven from a worm on the flywheel shaft takes up the oil from the sump through a large gauze strainer attached to the pump and delivers it into a pipe leading to a release valve. By means of this valve, which is adjustable, the oil pressure is con┬Čtrolled to the degree required. Any excess pressure is released past the valve and the oil goes back into the sump through one of the oil unions that holds the release valve body to the crankcase.

Do not alter the setting of the pressure adjusting screw without good reason, or before reading the directions on page 8.

From the pressure release valve body oil is taken by an external pipe to the oil filter chamber fitted behind and below the clutch housing (Fig. 6).

The chamber contains a Tecalemit fabric filter element (No. FG2368) through which the oil must pass in order to get out through the outlet pipe attached to the side of the filter chamber or body.

The outlet pipe leads back to the crankcase and to a distributor block inside. From here three pipes take the oil under pressure to the various bearings, and gears, etc. One pipe leads to the flywheel shaft bearing through which the oil gets along the flywheel shaft to the steady bearing at the front end. The second pipe leads to the crankcase rear bearing, and a drilling above the bearing takes a supply to the camshaft rear end bearing, along the camshaft, and to the front end bush (Fig. 20).

In addition to supplying the main and camshaft bearings the oil goes into drillings in the crank webs and into the crankpins to lubricate the big end bearings. The rotating crank dissipates the oil from the big ends to lubricate the cylinders, pistons, little ends, and cams, etc.

The third pipe takes a supply of oil to the bearing supporting the timing pinion collar in the reduction gear plate, and a small hole in the plate directs a jet of oil on to the reduction gears. The pipe extends to feed the overhead rocker gear, and finally the open end directs oil into the rear bearing of the reduction gear shaft (Fig. 35).