Before adjusting the valves, thoroughly warm up the engine.
Overhead Camshaft 6-Cylinder Engines
The OHC six-cylinder engine is equipped with automatic valve lash adjusters. No adjustment is necessary or possible.
Overhead Valve 6- and 8-Cylinder EnginesEXCEPT RAM AIR AND SUPER DUTY MODELS
No adjustment is necessary on these hydraulic lifters. If the engine has been disassembled, use the preliminary and final valve adjustment procedures in Engine And Engine Overhaul .RAM AIR IV AND SUPER DUTY MODELS
By their design characteristics, these engines may require an occasional adjustment. To adjust these limited travel lifters proceed as follows. If the engine has been disassembled use the preliminary procedure in Engine And Engine Overhaul first.
- Start the engine and tighten the rocker arm on any valve that is clattering. Tighten until the noise just disappears.
- Allow the engine to run until normal operating temperature is reached, then loosen each rocker arm adjusting nut until the clattering begins again. Retighten the nut until the noise disappears (this brings the pushrod slightly into the top of lifter travel) and, with the adjusting nut in this position, tighten the locknut to 30-40 ft. lbs.