What should oil pressure be? Mine below 40. Knocks on a pull, when pressure above 40 no knock. Sounds like a rod bearing? 123 oo mileage.

 

Typically, most manufacturers want to see a minimum 10 PSI at idle, on a fully warmed up motor, and then 10 PSI more / 1000 RPM.

My take on it is: If your pressure is that low at idle, then you need to rebuild the motor. If you are getting rod knock at low RPM, that also means its time for a rebuild.

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