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I thought that when main bearings go bad, pressure drops when you rev the engine. My pressure is at 0, but it goes up to 20-25 pounds when the engine is revved.

2006-12-02 05:11:31 · 8 answers · asked by jeff_is_sexy 4 in Cars & Transportation Maintenance & Repairs

There are no bad noises, just a slight ping on acceleration, almost like spark knock. To drive the car home, I bought some Lucas oil stabilizer and dumped about half the bottle in. You're supposed to do the whole bottle, but I didn't want to overfill too badly. That helped the engine maintain about 7 pounds at idle while warm.

The engine operates under ideal oil pressure while it's cold, but as it warms up (before I added the Lucas) it drops to zero at idle, raising only when the RPMs increase.

This whole thing seems fishy to me. It would seem that the car would run badly or not at all with spun bearings, but it runs fine. Like I said, I drove it all the way home (10 miles or so) with the Lucas.

2006-12-02 05:26:55 · update #1

8 answers

when my van did this years ago, it was caused by the fuel mix leaning out at freeway speeds which burned holes in the aluminum pistons.

2006-12-02 05:39:49 · answer #1 · answered by Tim 47 7 · 2 0

How old is the engine and how many miles? About 10+ years ago I had a 1977 Chevy P/U with at 305 that had 0 psi at idle when warm and about 25 psi at about 2000 rpm. The truck ran fine and I wouldn't have even known about it but I installed the gauge. I would suggest running higher viscosity oil to get higher pressure - like 20W-50. It's going lower your fuel mileage and make it harder to start when cold, but will raise your oil pressure. Or you could just keep driving it and at some point it will die. It could be years though.

2006-12-02 16:15:09 · answer #2 · answered by Stu 3 · 0 0

mechanical gage, with the plastic line that puts actual oil pressure at the gage, or electric that has a sensor screwed into the motor and a wire hooked to it? If the latter, replace the sensor. Unless you are hearing bad valve clatter and knocking at idle, you have oil pressure.. And you're right, when the bearings go bad you are fair at an idle, and it drops as the RPMs increase.

2006-12-02 13:19:20 · answer #3 · answered by oklatom 7 · 0 0

ya , check the pressure gauge with a test gauge. then check the oil pump - a high volume one can be put in some engines. this will help bring the pressure up. likely the eb\ngine bearing are worn . then put in heavy grade oil , stp and sell the car to some rude person deserving trouble

2006-12-02 13:36:13 · answer #4 · answered by tired out worker 1 · 0 0

How long has it been since you changed your oil? The older it is the pressure will be lower at idle and will increase with RPM. The other problem will be the sending unit which wil require you to change it.

2006-12-02 13:35:52 · answer #5 · answered by victor m 1 · 0 0

Just loose, old bearings. The main bearings typically cause low oil pressure. You can probably still drive it a long time with no problems.

2006-12-02 13:58:01 · answer #6 · answered by Anonymous · 0 0

Engine needs new oil pressure sender first and if that is the answer OK...if that doesn't fix it then you need a new gauge, lines and some new oil in the motor

2006-12-02 13:36:07 · answer #7 · answered by XTX 7 · 0 0

Rings are bad, check for blow by and plan on a rebuild very soon.

2006-12-02 13:32:25 · answer #8 · answered by ebay junkie 2 · 0 0

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