88 prostar oil pressure

[90pony]

just bought 88 prostar(351w) after engine warms up the oil pressure drops while the engine is idling and the warning buzzer goes off. while running at speed the oil pressure is good and no buzzer any one know anything about this

[Muttley]

Well, if you've got oil and it's running well and the temperature is normal, my guess would be the sending unit for the gauge.

[pkskier]

Don't know what oil or oil wt. you are using, but you may need to changed to 20W-50, whtich is what I run in my '87.

[90pony]

Thanks you may be right I just talked to a mechanic and i put 10w-40 in right after i bought it
He said they are supposed to run sae 30

[90pony]

Changed the oil to sae 30 and went to try it out same thing oil pressure dropped after running for a few minutes. Now ive changed the sending unit and the oil pressure gauge reads 80 lbs while running running in the driveway. did i get the wrong sending unit or is this right.

[pkskier]

Don't know where you bought it, but I changed mine a few years ago with one I bought at an auto parts store and it pegged the gauge out. Ordered the correct one from skidim.

[90pony]

I was afraid of that. Thats what it did, pegged the gauge. Its getting a false reading.Did the correct sending unit make the gauge not bounce around?

[pkskier]

When I switched to 20w50 oil is when the bounce stopped and mined would only bounce after a hard run, from the way it was explain to me the 10w30 was thinning out too much and could not hold a good oil pressure. I changed the sending you when I was not getting a reading at all, which can put a scare in you when it happens.

[90pony]

thanks,i just dont want to tear up something major