So lets say you have been driving around in traffic, got the car home and you see the gage says 15psi in drive at abiout 850RPM. You click it into nuetral, and it goes to 22PSI IS this normal on a rebuild that has abotu 1500 miles on it. By the way i run 10w-30 i the thing and the motor runs pretty healthy. In the summer months what do most people run for oil? 10w 40, 20w50, straight weight oils?o No:
If I recall, the stock idiot light comes on at 7 psi. The general rule of theumb is 10 psi per 1,000 rpm. Frankly I'm startled by reports of 40 psi at idle some guys relate. I'm pretty sure I make about 12 at idle in park and this is on a street driven daily driver. No problems in 4 years since the rebuildo No: Can i be the only guy around with "low" pressure that doesn't have a problem? I can't beleive that Buick worried about 15 psi when these things were new. I'm not an expert and maybe I'm way off base, but I don't think you have a problem.
A lot of things come to mind, do you know what the bearing clearances are (rods, main, AND cam bearings)? At least from the rebuild time? Was it machined on the tight end of spec, or looser for street/strip? It might be that you just need a thicker oil. Maybe try 10w40, 20w50, or just straight 30 (in order of increasing thinkness). You could check the pressure relief valve to see if it is stuck open, or needing shimming for increased pressure. Do you have an adjustable? An oil cooler could help raise pressure, if the oil is getting excessively hot and thinning. Here's a good link on oil viscosity: http://www.popularmechanics.com/automotive/auto_technology/2002/8/motor_oil/index.phtml page 3 is GOOD. Engine bearings: http://www.engineparts.com/motorhead/techstuff/bearingfailures.htm# Some possible Buick oiling mods: http://www.buickperformance.com/oilflow.htm
I'm with Chris about the lower pressure #'s. I have about 12-14lbs at idle in gear(700rpms),this is with mobil 1 5w-30. I had about 5lbs more with 10w-30 castrol non syn. Been this way for 20k miles. As long as the pressure come right up there is no need to worrie, yes these pressure numbers you are seeing are normal, I see no problems.
Ditto here... 10w30 oil... 12lbs (roundabout) at idle, maybe 15 in park. 6yrs of constant abuse and no probs yet. :TU: :TU: I woulnd't worry unless it dropped below 10lbs.... My first rebuild did that within the first 3000miles come to find out it went through the rod bearings:af: If your really worried about it, take off the oil filter and look to see if there is any bronze "grit" in the oil, That might be a sign of failing bearings. (at least that's what mine looked like:ball: ) Good luck:TU:
