AIR INLET AND EXHAUST SYSTEM
TM 5-3805-263-14&P-2
CYLINDER HEAD AND VALVES
There is one cylinder head for all four cylinders.
Each cylinder has one intake and one exhaust valve.
The cylinder head has valve seats installed and
they can be replaced.
The valve guides can be replaced. There are
threads on the inside diameter of the valve guides to
hold oil that lubricates the valve stem.
VALVES AND VALVE MECHANISM
The valves and valve mechanism control the flow
of air and exhaust gases in the cylinder during engine
operalion.
The intake and exhaust valves are opened and
closed by movement of these components; crank-
SYSTEMS OPERATION
shaft, camshaft, valve lifters (cam followers), push
rods, rocker arms and valve spring. Rotation of the
crankshaft causes rotation of the camshaft. The
camshaft gear is driven by, and timed to, a gear on
the front of the crankshaft. When the camshaft
turns, the cams on the camshaft also turn and cause
the valve lifter (cam followers) to go up and down.
This movement makes the push rods move the rocker
arms. The movement makes the push rods move the
rocker arms. The movement of the rocker arms will
make the intake and exhaust valves in the cylinder
head open according to the firing order (injection
sequence) of the engine. A valve spring for each valve
pushes the valve back to the closed position.
Valve rotators cause the valves to have rotation
while the engine is running. This rotation of the
valves keeps the deposit of carbon on the valves to a
minimum and gives the valves longer service life.
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