can someone tell me how to set up an oil pump for my Bigblock? I just through mine together and I was rewarded with 15 lbs at idle. what is the correct way? thanks Joe
I'm not sure what the problem is...how many psi were you expecting? 10 psi per 1,000 rpm is a general rule of thumb. Old Buick engines, or a fresh rebuild on one, with tolerances going out on the timing cover or pump cover, see about 10, or less, at idle. On mine, when I rebuilt it, I beleive that I saw 12 psi at 800 rpm. It didn't bother me a whit, and it didn't bother the A+P certified mechanic that I had with me, either. It also didn't bother the engine, because that was over 15,000 miles ago, and everything's still a go:TU: Is this 15 psi hot or cold? What's your idle rpm? Personally, I think you do not have a problem at all.
Oil Pump rebuild 1. Make sure that the front cover you use is not scored too badly to work. Look for bad wear patterns or scraping, chunks missing, etc. 2. Use the iron "booster plate" that T/A sells to replace the wear surface on the aluminum bottom cover of the pump. 3. Set the end clearance between the oil pump gears/impeller and the booster plate to two thousandths (.002"). Use the T/A "shim kit" of different thickness gaskets for this, mix and match until the clearance is right. Plastigage works for me to set and check this clearance. 4. External to the oil pump, main, rod, and cam bearing clearances will affect your oil pressure. I have about 10-15 PSI hot at idle, but my pressure maxes out at 35 PSI at cruise when the motor is hot due to big (.003) main clearances. It doesn't matter whether the cruise rpm is 2000 or 3000 - same pressure:eek2: !! This condition has existed for about 2 years and 8000 miles and I haven't scattered the bottom end yet, but I plan to do something about it this winter.
Its at 15 lbs at 160 degrees with a bumpy 650 idle. I would really prefer at least 20 but as long as the lifters don't bleed out on me I guess I'm satisified. when its cold the oil pressure is a solid 60 lbs, and I thought that was a big drop. when I say cold, I mean about 75-80 degrees.
