oil pressure!!!!!!
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oil pressure!!!!!!
hey everyone. just had a question about my oil pressure. my engine is just the 1.7 of course, but i am curious as to what my psi's should be in idle. i know that when my car is cold it reads really high, like in the 50's then after a while it will start to drop. anything helps. thank you
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Re: oil pressure!!!!!!
Hard to explain. Gotta have working knowledge of hydraulics and engines. Pressure is dynamic and changes depending on many factors.
Rule of thumb: It MUST have enough pressure to keep the idiot light OFF at all times the engine is running. (Normal RPM ranges. If you almost stall the engine by dumping the clutch too fast, the idiot light may come on because the engine slowed way down.)
Rule of thumb: Oil pressure is a direct function of engine RPM (oil pump speed). (Pump makes pressure, leakage loses pressure. Example: every bearing is a leak point. Pump has to be able to outrun the leaks (volume) in order to keep sufficient pressure up.)
Rule of thumb: Cold oil pressure is always higher than hot oil pressure for any given RPM range (up to the regulated max pressure). Oil thins out as it heats up, pressure drops as a direct result of the thinning. Oil and coolant temps do not necessarily have to agree, so the coolant temp gauge might show normal temp but the oil might not be up there yet.
Rule of thumb: The pressure regulator in the oil pump ONLY regulates (limits) the maximum pressure. Nothing else.
Generally desired, but NOT always true: At least 1 PSI for every 100 RPM of idle speed....i.e. 700 RPM = 7 PSI..... (Again, this is not a rule, and not always true.)
Did that answer anything?
Rule of thumb: It MUST have enough pressure to keep the idiot light OFF at all times the engine is running. (Normal RPM ranges. If you almost stall the engine by dumping the clutch too fast, the idiot light may come on because the engine slowed way down.)
Rule of thumb: Oil pressure is a direct function of engine RPM (oil pump speed). (Pump makes pressure, leakage loses pressure. Example: every bearing is a leak point. Pump has to be able to outrun the leaks (volume) in order to keep sufficient pressure up.)
Rule of thumb: Cold oil pressure is always higher than hot oil pressure for any given RPM range (up to the regulated max pressure). Oil thins out as it heats up, pressure drops as a direct result of the thinning. Oil and coolant temps do not necessarily have to agree, so the coolant temp gauge might show normal temp but the oil might not be up there yet.
Rule of thumb: The pressure regulator in the oil pump ONLY regulates (limits) the maximum pressure. Nothing else.
Generally desired, but NOT always true: At least 1 PSI for every 100 RPM of idle speed....i.e. 700 RPM = 7 PSI..... (Again, this is not a rule, and not always true.)
Did that answer anything?
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