Re: Any reason for low oil press at low rpm besides the pump?

Didn't I say that?

Spec:

1. Measure Oil Pressure

Oil pressure: At idle speed: 0.3 kg/cm3 (4.3 psi) At 3,000 RPM: 2.5 - 5.0 kg/cm# (36 - 71 psi)

This engine has kind of a low spec. My Supra has an oil pressure gauge, and if it's accurate at all, my car falls in spec. I think it's low, but it's in spec.

NOTE: after hard driving with the engine fully warm, oil pressure will drop a bit. Use a heavier weight oil like 10-40 or 'diesel' oil, 15-40.

What did you do for a rebuild?

Also, why rebuild an engine and not replace the oil pump?!?!?

That engine is a real PITA to get to the oil pump! Should have done it when you had the engine out!

"Jeff Strickland" wrote in news:hekg2i$q4b$ snipped-for-privacy@news.eternal-september.org:

It always seems to be top-posters doesn't it?

If all you want is high pressure, use 20w50. I used 20w50 in my Jeep for summer in Southern California, but I'm positive that if 20w50 works for anybody anywhere else in the world, engine troubles are close at hand. I found the 20w50 in my 258 Inline 6 was slow to get to the top of the motor. I used it exactly one oil change. The upside is, the leaks stopped while I used it.

The spec you give is a little under 10psi per 1000rpm at idle and a bit over at highway speeds. Since the question is about idle speed pressure dropping, if he's got 10psi at idle, then all is well in his universe.

I resemble that remark ... ;-)

When the low oil pressure warning light comes on, the first thing to check is oil volume with the dipstick to make sure there is sufficient oil in the oil pan.

Next, check the oil sender for leaks because a visual check costs nothing, even though the symptoms you are describing don't point to a leaking oil sender.

Is the oil sender is not leaking, remove the sender and install an oil pressure gauge to measure actual oil pressure, using the figures hachiroku posted.

Whoever rebuilt the engine should have measured the clearances between the impeller, crescent, and body of the oil pump before reusing it. Whatever caused the original engine to fail could have also caused oil pump wear.

The other thing to do when rebuilding an engine is to plasti-gauge the main and connecting rod bearings to make sure there isn't excess clearance, which can cause low oil pressure.

Install a REAL oil pressure gauge and see what you have.

The spec I found here says 15W-40 oil for that engine for normal use and

Wow. For a 7M-GE?!?!?

I'll be dipped!

Engine Oil Recommended viscosity: 20-100F 15w40-20w50, 0-80F 10w30-10w50, 50F and below 5w30

I've been running 10W-40, and I only use the car in the summer.

Autoparts places have the oil pump ...

And make sure you're checking the oil, not the trans. Believe me, it happens.

--Vic