Section X. CAMSHAFT AND CAMSHAFT BEARINGS
7-21. General. The camshaft is supported on large
diameter, pressure-lubricated, removable bearings in the
crankcase. The camshaft is driven by the camshaft gear
which meshes with the crankshaft gear. The crankshaft
gear and camshaft gear each have timing marks for
proper assembly of the camshaft to produce the proper
firing order and operation of the rocker arm assembly.
The camshaft operates the rocker arms in the proper
order via the valve tappets and pushrods. A toothed
portion of the camshaft, located near the center of the
camshaft, engages with and drives the oil pump gear.
7-22. Camshaft and Camshaft Bearings.
a. Removal and Disassembly.
Figure 7-51. Thrust plate mounting bolts, removal and
(1) Remove the engine from the unit (para 5-12 and
(7) Remove the thrust plate mounting bolt and
washer assembly and pull the camshaft
assembly forward out of the cylinder block as
(5) Remove the cylinder head cover and rocker arm
from cylinder block.
It is necessary for removal of the
camshaft that the valve tappets be in
the raised position. To accomplish
this, set the engine on the
bellhousing or upside down (support
the engine on suitable blocks so that
cylinder head studs clear), and push
the tappets to raised position.
Figure 7-52. Camshaft and thrust plate, removal and
(6) With the tappets in the raised position, rotate the
engine crankshaft until the two holes in the
camshaft gear expose the thrust plate mounting
(8) Remove the camshaft bearings (4, 5, figure
If the bearings cannot
hand, drive out the camshaft bearings (4, 5) with
a brass drift. If difficulties are encountered
removing the rear camshaft bearing, it may be
necessary to remove the bellhousing (para