no oil pressure
#1
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Last time I had the boat. Started engine idel at 50 psi oil pressure after warming up it dropped to 30 psi running 3800 rpm (30 psi oil) for a 1/2 hour then back to 1000 rpm the oil pressure dropped to 0 psi then I revved it to about 2000 rpm then back to 1000 rpm and the oil pressure went up and held at 15 psi. the engine has no knocks and seems to run fine.
what's wrong
1. spun bearing
2. oil pump warn out
3. oil pump pressure regulater stuck or weak.
what's wrong
1. spun bearing
2. oil pump warn out
3. oil pump pressure regulater stuck or weak.
#2
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My Gen 6 502 had always held good oil pressure. Last fall after a hard run I brought it back to idle gradually. The alarm went off and I checked the gage as I reached for the key, it showed zero. Shut it down and checked everything, temp was normal, level OK, odor of everything seemed OK. Started it back up and oil pressure was fine. I then changed the oil and ran the remainder of the season, probably 10 trips with 10 or stop/start each time. All was well.
Over the winter I had the engine out for some other upgrades and change the oil pump just for grins. The pan was spotless inside as well as the internals. It has never happened again. I suspect that the spring in the pump just hung up for SFR.
Since then I have not used the oil filters with the anti drain back valve. No need to since it is holes up anyway. Always wondered if that had anything to do with it.
Over the winter I had the engine out for some other upgrades and change the oil pump just for grins. The pan was spotless inside as well as the internals. It has never happened again. I suspect that the spring in the pump just hung up for SFR.
Since then I have not used the oil filters with the anti drain back valve. No need to since it is holes up anyway. Always wondered if that had anything to do with it.
Last edited by BadDog; 08-14-2003 at 02:51 PM.
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I'd temporary a mechanical gauge to see if it's a electrical problem. If not, I wouldn't be running the engine.
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How many hours does the motor have? I agree with Cord you are only going to create heat by not having any oil pressure. Now if you have many hours and the gauge is functioning properly and the motor seems to run fine then i would say your main berings are wearing a little thin?
1) I do not think it was a spun bering you motor would not run than long.
2) If it is your oil pump, then you have to pull the motor and since you are that far you might as replace the berings at that time.
You need to change your oil and look for bering fragments or signs of wear.
Give us some more specs on your motor, was it recently rebuilt how long ago, how many hours do you have on it now?
Good luck,
1) I do not think it was a spun bering you motor would not run than long.
2) If it is your oil pump, then you have to pull the motor and since you are that far you might as replace the berings at that time.
You need to change your oil and look for bering fragments or signs of wear.
Give us some more specs on your motor, was it recently rebuilt how long ago, how many hours do you have on it now?
Good luck,
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15 hours on the motors
The gauge works because the motor shut down due the oil pressure switch that is connected fuel pump. 0 oil pressure 0 gas flow... I will dbl. check with mech gauge to be sure.
The gauge works because the motor shut down due the oil pressure switch that is connected fuel pump. 0 oil pressure 0 gas flow... I will dbl. check with mech gauge to be sure.
Last edited by seahawk; 08-14-2003 at 05:26 PM.
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cord is right, remove the oil sendor and screw in a mech. oil pressure gauge, your gauge are sensor might be out of calibration, if the mech. oil gauge shows low oil pressure then take a look inside, i would cut open your oil filter, check for metal and bearing parts,
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1) make sure the distributor is turning.
2) try a new filter
3) if that works find the source of the water that is winding up in the oil. You can also change to a filter with synthetic media that will not swell from the moisture.
As H2Xmark says cut your old filter open and inspect for metal particles.
3) If that does not work, pull the engine apart and find out, possibly the pickup is lying in the bottom of the pan.
2) try a new filter
3) if that works find the source of the water that is winding up in the oil. You can also change to a filter with synthetic media that will not swell from the moisture.
As H2Xmark says cut your old filter open and inspect for metal particles.
3) If that does not work, pull the engine apart and find out, possibly the pickup is lying in the bottom of the pan.
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