m. The Cylinder Head (Fig. 12). The cylinder head is a one-piece
casting that bolts to the block and you can remove or install the
cylinder from the engine as an assembly.
It contains the exhaust
four exhaust valves and press fitted valve seats provided for each
For cooling, each fuel injector is inserted into a thin walled tube
that passes through and the water space in the cylinder head
The exhaust passages from the exhaust valves of each
cylinder lead through a single port to the exhaust manifold and
engine coolant surrounds it. Additionally, spray nozzles ensure the
cooling of high heat areas, installed between each pair of cylinders
in the coolant inlet ports. These nozzles direct coolant against the
portions of the head subject to greatest heat. The fuel supply and
return manifolds are an integral part of the cylinder head and have
tapped holes for fuel tube connections.
Excess oil from the valve
and injection mechanisms lubricate the exhaust valves.
n. The Exhaust Valves and Fuel Injector Operating Mechanisms
(Fig. 12). Each cylinder has three rocker arms. The outer two arms
operate the exhaust valves, and the center arm operates the fuel
Each set of rocker arm assemblies pivots on a shaft
supported by two brackets; bolts secure each bracket to the head.
Removal of the bracket bolts permits the rocker arm assembly to be
raised providing access to the fuel injector and exhaust valve
springs. The camshaft, through cam followers and push rods extending
through the cylinder head, operates the rocker arms.
follower operates in a bore in the head.
Through a passage in the
cylinder head and drilled rocker arm bolts and arm shaft, oil from
the cylinder block lubricates the mechanism.
Excess oil from the
rocker arms lubricates the exhaust valves and cam followers.
from the camshaft bushing bores provides additional lubrication.
o. The Control Tube Assembly (Fig. 12). A control tube assembly
mounts on each cylinder head assembly. It controls the amount of the
fuel injected into the cylinders.
p. The Throttle Delay Cylinder. The delay cylinder mounts on the
right head only.
accelerates, reducing exhaust smoke and improving fuel economy.