CYLINDER HEAD AND VALVES
SYSTEMS OPERATION
(75V1-75V1446, 90N1-90N6120)
CYLINDER HEAD AND VALVES
Engines with Serial Numbers 75V1-75V1446, 90N1-90N6120
CYLINDER HEAD AND VALVES
1. Push Rod. 2. Cam follower. 3. Guide support. 4. Rocker arm shaft. 5. Rocker arm. 6. Exhaust valve. 7.
Valve seat insert. 8. Intake Valve. 9. Inner valve spring. 10. Outer valve spring.
and exhaust valves in the cylinder head open and close
The valves and valve system components control
according to the firing order (injection sequence) of the
the flow of inlet air and exhaust gases into and out of the
engine. Two valve springs for each valve help to hold the
cylinder during engine operation.
valves in the closed position.
The intake and exhaust valves are opened and
There is one intake and one exhaust valve for each
closed by movement of these components; crank- shaft
cylinder. The valve seat insert for the exhaust valve can
camshaft cam followers push rods rocker arms and
have replacement. The valve seat for the intake valve is
valve springs. Rotation of the crankshaft causes rotation
machined in and is a part of the cylinder head. When the
of the camshaft. The camshaft gear is driven by and
seat for the intake valve has been machined to the limits
timed to a gear on the front of the crankshaft. When the
given in the SPECIFICATIONS
it can be bored
camshaft turns the cams on the camshaft also turn and
(machined) for a valve seat insert. The valve guide bore
cause the cam followers to go up and down. This
is machined in and is a part of the cylinder head.
movement makes the push rods move the rocker arms.
The movement of the rocker arms will make the intake
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