1.2.1
Valve Operating Mechanism
DETROIT DIESEL 53
Inspection
Wash the rocker arms, rocker arm shaft and brackets
thoroughly in clean fuel oil and dry them with
compressed air. Make certain that the oil passages in
the rocker arms, rocker arm shaft and bracket bolts
are open and clean.
Inspect all of the parts for excessive wear.
The maximum clearance between the rocker arm shaft
and the injector rocker arm bushing or an exhaust
valve rocker arm (which has no bushing) is .004 " with
used parts.
Examine each rocker arm pallet (contact face) for
wear or galling. Also check the contact surfaces of the
exhaust valve bridge (four valve cylinder heads).
Remove Cam Follower and Push Rod Assembly
(Cylinder Head Removed from Engine)
With the cylinder head removed from the engine,
remove the cam followers as follows:
1. Rest the cylinder head on its side and remove the
two bolts and lock washers securing the cam follower
guide to the bottom of the cylinder head (Fig. 2).
Fig. 6 - Former and Current Cam Followers
Remove the guide.
1. Clean and remove the valve rocker cover.
2. Pull the cam followers from the bottom of the
cylinder head.
2. Remove the fuel pipes from the injector and the
fuel connectors.
3. Remove the fuel pipes from the injector and the
fuel connectors.
3. Remove the rocker arm brackets and rocker arm
4. Loosen the lock nuts at the upper end of the push
shaft as outlined in Steps 3 and 4 under Remove
rods and unscrew the push rods from the rocker arm
Rocker Arms and Rocker Arm Shaft.
clevises.
4. Loosen the lock nut at the upper end of the push
5. Pull the push rod and spring assemblies from the
rod, next to the clevis, and unscrew the rocker arm
bottom of the cylinder head.
from the push rod to be removed. Remove the lock nut
6. Remove the push rod lock nut, upper spring seat,
from the push rod.
spring and lower spring seat from each push rod for
cleaning and inspection.
5. Install the remover J 3092-01, a flat washer and nut
on the push rod (Fig. 3). Screw the nut down on the
The push rod spring seat retainers remain in the
end of the push rod to compress the push rod spring.
cylinder head. If the head is to be changed, these
retainers must be removed and installed in the new
head.
6. Remove the retainer from the cylinder head with a
screw driver or similar tool as shown in Fig. 3.
Remove Cam Follower and Push Rod Assembly
7. Unscrew the nut at the outer end of the push rod,
(Cylinder Hood Not Removed from Engine)
thus releasing the spring.
A push rod, push rod spring, spring seats and cam
8. Pull the push rod, spring, spring seats and cam
follower may be removed from the top of the cylinder
head by using tool J 3092-01 as shown in Fig. 3.
follower out through the top of the cylinder head.
SEC. 1.2.1 Page 3
July, 1972
