Lifter / Lash Adjuster: Service and Repair

Fig. 5 Exploded View Of Hydraulic Valve Lifter:

Failure of a hydraulic valve lifter, Fig. 5, is generally caused by an inadequate oil supply or dirt. An air leak at the intake side of the oil pump or too much oil in the engine will cause air bubbles in the oil supply to the lifters causing them to collapse. This is a probable cause of trouble if several lifters fail to function, but air in the oil is an unlikely cause of failure of a single unit.
Valve lifters can be removed after removing rocker arm cover and pushrod cover. Loosen rocker arm stud nut and rotate rocker arm so that pushrod can be removed, then remove valve lifter.

DISASSEMBLY
1. Depress plunger with a pushrod, then remove pushrod seat retainer, Fig. 5, using a suitable screwdriver.
2. Remove pushrod seat, metering valve, plunger, plunger spring and ball check valve assembly.
3. Pry ball retainer loose from plunger and remove ball check valve and spring using a small screwdriver.

CLEANING & INSPECTION
1. Clean all lifter components in suitable solvent.
2. Inspect all parts for wear or damage. If any one component is worn or damaged, the entire assembly must be replaced.
3. If lifter body wall is worn, inspect cylinder block lifter bore.
4. If bottom of lifter is worn, inspect camshaft lobe.
5. If pushrod seat is worn, inspect pushrod.

ASSEMBLY
1. Position check ball on small hole in bottom of plunger, then install spring and ball retainer.
2. Install plunger spring over ball retainer, then slide lifter body over spring and plunger. Ensure oil holes in lifter body and plunger are aligned.
3. Fill assembly with SAE 10 oil, then depress plunger with a 1/8 inch drift pin. Insert a 1/16 inch drift pin through both oil holes to hold plunger down against spring tension.
4. Remove the 1/8 inch drift pin and refill assembly with SAE 10 oil, then install metering valve and pushrod seat.
5. Install pushrod seat retainer, then push down on pushrod seat and remove 1/16 inch drift pin from oil holes.