Engine Diagnosis - Mechanical

MECHANICAL

ENGINE MECHANICAL DIAGNOSIS CHART










Lifter Purge Guideline

1. Warm engine to standard idle conditions.

NOTE: Engine noise may be in the form of a clicking, chatter, or clattering noise.

2. Listen to the engine for 30 to 60 seconds with the hood up and the engine cover removed.

3. If noise is present, de-aeration of the lifters is required.

4. Run the engine between 2000 and 3000 RPM for three to five minutes.

5. Return the engine to standard idle speed for 30 to 60 seconds.

6. Evaluate noise. If noise is present, repeat the run an additional 4 cycles.

NOTE: The standard drive cycle will be about 10 - 15 miles of non- stop, combined highway and city driving.

7. If noise is present, take the vehicle on a standard drive cycle.

NOTE: Use a feeler gauge to verify clearance is present between the lifter and cam base circle.

8. Evaluate the noise. If noise present, follow standard service procedure for lifter repairs or noise conditions.
9. Evaluate lifters for sponginess, check valve defects, and clearance.