On a rebuilt engine with relatively low mileage, oil leakage past the valve guide seals is a more likely cause of oil consumption than leakage past piston rings.

Question

Quizplus · Accepted Answer

Valve guide seals can start leaking oil into the combustion chamber, causing oil consumption, even on a rebuilt engine with low mileage, especially if the seals were not replaced or installed correctly during the rebuild. Leakage past piston rings typically occurs with higher mileage or wear.

On a Rebuilt Engine with Relatively Low Mileage, Oil Leakage