Engine

The following component tests are used to diagnose valve train concerns.

Valve Train Analysis - Engine Off, Valve Cover Removed

Check for damaged or severely worn parts and correct assembly. Make sure correct parts are used with the static engine analysis as follows.

Valve Train Analysis - Camshafts and Valve Tappets

Check for broken or damaged parts. Check for loose mounting bolts on camshaft caps. Check for worn or damaged valve tappets.

Valve Train Analysis - Valve Springs, Valve Tappets Removed

Check for broken or damaged parts.

Valve Train Analysis - Valve Spring Retainer and Valve Spring Retainer Keys, Valve Tappets Removed

Check for correct seating of the valve spring retainer key on the valve stem and in valve spring retainer. Check for correct seating on the valve stem.

Valve Train Analysis - Valves and Cylinder Head, Valve Tappets Removed

Check for plugged oil drain back holes. Check for worn or damaged valve tips.

Valve Train Analysis - Camshaft Lobe Lift

Check the lift of each camshaft lobe in consecutive order and make a note of the readings.

1. Remove the spark plugs. Refer to the appropriate 303-07 section.

2. Install the Dial Indicator Gauge with Holding Fixture so the rounded tip of the dial indicator is on top of the camshaft lobe and on the same plane as the valve tappet.

3. NOTICE: Only rotate the crankshaft clockwise. If the engine is rotated counterclockwise the valve

train timing may slip resulting in the engine having to be retimed.

Rotate the crankshaft using a breaker bar and socket attached to the crankshaft pulley retainer bolt. Rotate the crankshaft until the base circle of the camshaft lobe is reached.