Oil Pump Questions:

Q:  Why do I have low oil pressure?

A: This is commonly caused by increased clearances within the engine, i.e., worn engine.  It could also be caused by low oil levels and by the oil pump ingesting air, or because the by-pass valve is not functioning properly. 

Q:  Why do I have high oil pressure?

A:  Can be caused by using the wrong viscosity (thickness) of motor oil in your engine, or because the by-pass valve is not functioning properly.  Another common cause is tight engine clearances, i.e., new engine. Refer to your owner’s manual for the correct viscosity of oil for the climate conditions you drive in.

Q:  Can I adjust or change the oil pressure?

A:  Only the by-pass pressure can be changed by changing the by-pass spring, not the idle pressure.  Some of our Melling Select Performance oil pumps offer spring options.

Q:  How far from the bottom of the pan should my screen be?

A:  Oil pump pick-up screens need to be 3/8” to ½” from the bottom of the pan.

Q:  How should I break in my camshaft?

A:  Start the engine, after it starts, check for oil pressure and bring the RPM to 1500-2000.  If the pressure is good, run the engine at this RPM range for 20 minutes.  After this run in period, final adjustments can be made and the engine put in service.

Q:  Will a hi-volume oil pump eliminate my low oil pressure?

A:  No, a hi-volume oil pump is not a band-aid.

Q:  Why does my oil pressure drop at high RPM’s?

A: The oil pump screen could be sucking air or oil is not returning to the pan properly.  Every situation is different, because every engine, and every engine builder, is different.  These are some of the more common occurrences we experience.