121. Hourmeter
a. Description. The mechanically operated hourmeter (4) is mounted on the cylinder head of the engine. The
hourmeter is driven by the oil pump. It converts the crankshaft speed into hours of running time. The hourmeter is sealed
at the factory. The hourmeter should not be repaired or disassembled.
b. Removal.
(1) Loosen the hourmeter clamp screw (3).
(2) Remove the hourmeter mounting screw (5) and lockwasher.
(3) Lift up the hourmeter (4) and remove it from the adapter (11).
(4) Remove the adapter mounting screw (10) and remove the hourmeter adapter (11).
c. Installation.
(1) Install the hourmeter adapter (11) on the cylinder head and tighten the mounting screw (10).
(2) Install the hourmeter (4) and see that its shaft is properly connected with the oil pump drive shaft.
(3) Tighten the clamp screw (3).
(4) Install and tighten the mounting lockwasher and screw (5).
Section VIII. ENGINE LUBRICATION SYSTEM
122. Description
The lubrication system of the engine is of a pressure and splash type. An internally mounted oil pump is driven by the
camshaft and delivers the oil under pressure to the main and connecting rod bearings. The camshaft, pistons, cylinders,
valve tappets, and valve stems are lubricated by splash. The oil pump forces oil through the oil filter, which traps sediment
and dirt. The lubricating system consists of the crankcase filler tube, oil level gage, oil filter, oil pump, oil pressure relief
valve, oil pan, electric oil pressure adapter, oil pressure gage, and oil lines.
123. Oil Filter
a. Removal.
(1) Remove the oil filter drain plug (18) at the bottom of the oil filter body (7) and drain the oil and sediment from
the oil filter.
(2) Unscrew the fitting nut of the filter inlet hose (23) and disconnect the hose from the inlet elbow (19).
(3) Unscrew the fitting nut of the filter outlet hose (20) and disconnect the hose from the filter outlet elbow (21).
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