DETROIT DIESEL 53
Valve Operating Mechanism 1.2.1
Fig. 9. - Checking the Clearance Between the
Cam Follower Guide and Cam Follower Legs
on its pin and the roller must be free from flat spots or
scuff marks. If the roller does not turn freely or has
been scored or worn flat, then examine the cam on
which it operates. If the cam is excessively worn or
damaged, replace the camshaft.
Measure the total clearance between the roller bushing
and pin, crosswise of the pin, as shown in Fig. 5 and, if
the bushing is worn to the extent that more than
Fig. 8. - Valve and Injector Operating
Mechanism Details and Relative Location of
to make sure they are clean, smooth and free of score
marks to permit proper functioning of the cam followers.
Any existing score marks must be cleaned up.
Check the cam follower-to-cylinder head clearance.
The clearance must not exceed .006 " with used parts.
The cam follower roller must turn smoothly and freely
Fig. 10. - Adjusting Cam Follower Guide
1972 General Motors Corp.
SEC 1.2.1 Page 5