Help with my oil pressure problems
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Joined: May 2009
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Help with my oil pressure problems
I bought a re manufactured 2.9l engine for my ranger about a year ago. i put it in back in july of 08 and around the first of the year my ranger started to lose oil pressure. at first i thought it might be the oil pump or maybe the sending unit. i wen and replaced them. but now when i am running the truck for about fifteen minutes and it warms up i lose all oil pressure. i took the valve cover off and it has no oil on the top of the engine once it has warmed up. i dont know what to do and i already have alot of money in this ranger becaue i put a lift on it and redid the front and rear ends its nice i just cant figure out why i lose the oil pressure. i was thinkin mayb the main berring or mayb the cam. i am lost please help
Thanks
Thanks
Logistics Pro
Joined: Jan 2002
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From: suburban atlanta
The oil will not even be close to getting thinned out from heat after running for only 15 minutes. For that reason, I would say it is not the oil.
When you installed it, what pan gasket did you use? Some of the 'cork smushed together' gaskets were reported to fail and clog the pump intake screen. The rubbery ones don't seem to have that problem.
Are you checking the pressure with a mechanical gauge or the gauge on the dash? Depending on vintage, the dash gauge is just an on-off indicator. The sending unit for a real gauge needs a 'dome' for the diaphragm and moving sweep arm to change the resistance. If your sending unit is a small metal and black plastic device, it is just an on/off switch, and there is a resistor on the printed circuit to fake 'medium' pressure.
Oil pumps are the best lubricated mechanism in an engine, and only fail infrequently.
tom
When you installed it, what pan gasket did you use? Some of the 'cork smushed together' gaskets were reported to fail and clog the pump intake screen. The rubbery ones don't seem to have that problem.
Are you checking the pressure with a mechanical gauge or the gauge on the dash? Depending on vintage, the dash gauge is just an on-off indicator. The sending unit for a real gauge needs a 'dome' for the diaphragm and moving sweep arm to change the resistance. If your sending unit is a small metal and black plastic device, it is just an on/off switch, and there is a resistor on the printed circuit to fake 'medium' pressure.
Oil pumps are the best lubricated mechanism in an engine, and only fail infrequently.
tom
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I used a Rubber Gasket. and i have not used a mechanical gauge yet i will try that next. the reason i think it might be something in the engine is because when the oil pressure drops i start to get a knock on the top end of the motor
Post Fiend
Joined: Nov 2008
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From: McKenzie River
Still sounds like oil starvation due to a borderline pump or obstructed pump.
Logistics Pro
Joined: Jan 2002
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From: suburban atlanta
The 2.9 has hydraulic lifters -- that'll cause a knock if they are starved. The drive gear on the bottom of the distributor may not be a true hex any more, or the driven oil pump shaft may be rounded off. Easily inspected. Well, relatively...
Seems as if the pump is not delivering, unless a gallery plug fell out. I don't have any particular one in mind, but this was a rebuilt engine, and they generally replace the plugs after cleaning and doing all the block work. You could have a plug on the front of the block behind the timing chain cover that popped out, and is allowing all the oil to dump over the timing chain down into the sump, that would normally be feeding the lifters and rocker arms.
You could use an electric drill to run the pump with stuff open for inspection to see if there was an obvious blowout spot. Might even be able to hear it gushing around after running the pump and shutting it off.
tom
Seems as if the pump is not delivering, unless a gallery plug fell out. I don't have any particular one in mind, but this was a rebuilt engine, and they generally replace the plugs after cleaning and doing all the block work. You could have a plug on the front of the block behind the timing chain cover that popped out, and is allowing all the oil to dump over the timing chain down into the sump, that would normally be feeding the lifters and rocker arms.
You could use an electric drill to run the pump with stuff open for inspection to see if there was an obvious blowout spot. Might even be able to hear it gushing around after running the pump and shutting it off.
tom
