* Engine RPM: Oil pressure will be higher at higher RPMs.
* Oil Temperature: Pressure will generally be higher when the oil is cold and lower when it's hot.
* Oil Viscosity (weight): Thicker oil (higher weight, like 20W-50) will produce higher pressure than thinner oil (like 5W-30).
* Engine Wear: Worn bearings and other internal components can lead to lower oil pressure.
* Oil Pump Condition: A failing oil pump will result in low oil pressure.
General Guidelines:
A healthy 350 small-block Chevy engine should typically show:
* At idle (warm): 10-20 PSI is generally considered acceptable, although some engines might run slightly lower, especially if they have a slightly larger oil pump clearance. Anything significantly below 10 PSI at idle warrants investigation.
* At higher RPM (2000-2500 RPM, warm): 30-50 PSI is a typical range. Again, this can vary depending on the factors mentioned above.
Crucially: These are guidelines, not hard and fast rules. Consult your engine's specific service manual for the recommended oil pressure specifications. The manual will likely provide charts or tables showing acceptable pressure ranges at different RPMs and temperatures. Always prioritize the manufacturer's recommendations.
Low oil pressure is a serious problem and can lead to catastrophic engine damage. If you're experiencing low oil pressure, you need to investigate the cause immediately. Possible causes include low oil level, worn bearings, a faulty oil pump, or a clogged oil filter.
