Yukon 4WD V8-6.5L DSL Turbo VIN S (1997)
Rocker Arm Assembly: Service and Repair
Removal
NOTE:
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Rotate the engine until the mark on the crankshaft balancer is at 2 o'clock.
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Rotate the crankshaft counterclockwise 88 mm (31/2 inch), aligning the crankshaft balancer mark with the first lower water pump bolt about
12:30.
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This will position the engine so no valves are close to a piston crown.
1. Remove the valve rocker arm cover.
CAUTION: All valve train components must be reassembled in the exact order and position from which they were removed.
2. Remove the valve rocker arm shaft bolts.
3. Remove the valve rocker arm shaft with the valve rocker arms.
4. Remove the pushrods.
NOTE: The pushrods must be installed in the original direction as disassembly. This is because the pushrods have a different degree of hardness
at each end. A paint stripe identifies the upper end of the pushrod. If the paint stripe is not visible mark the pushrods on the upper end as they are
removed.
5. Remove the valve rocker arms, if required.
6. Insert a screwdriver into the valve rocker arm shaft bore and break off the end of the nylon valve rocker arm retainers.
7. Remove the valve rocker arm retainers with a pair of pliers.
8. Slide the valve rocker arms from the shaft.
9. Inspect each of the following components:
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Inspect the valve rocker arms and the shafts at their mating surfaces. These surfaces should be smooth and free from scoring or other damage.
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Inspect the valve rocker arm areas which contact the valve stems and the sockets which contact the pushrods. These areas: should be smooth
and free of damage and wear.
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Inspect the pushrods for bending. Roll the pushrod on a flat surface to determine if the pushrod is bent. Replace the pushrod if necessary.
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Inspect the ends of the pushrods for scoring or roughness.
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Inspect the valve lifter guides and the retainers.
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Inspect the oil passages in the pushrods for obstructions. The pushrod oil passages must be clean.
