Q: Oil was accidentally over filled.

asked by on March 17, 2017

Hi we added 5 litres of oil when it only takes 4.there is now a knocking sound which increases as you rev it up. What could it be

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Hi there. Wen the engine was overfilled by an additional quart of engine oil, then the engine was trying to lock up as the crankcase pressure was too high and the pistons are pressing against the oil. I recommend draining the engine oil and re-filling it to the properly level and listen for the knocking sound. If the noise goes away, then the engine is now okay, but if the noise continues to emit, then the pistons or bearings could have been damaged to the added stress from the extra oil. If you need further assistance with your engine knocking, then seek out a professional, such as one from Your Mechanic, to help you.

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