VandykeT/A

Before I messed with it I got 55psi or so cold start and then it would drop to just below 40 hot. Now I get right at 40 cold start and only drop to slightly below 40 idle. Mainly it just wants to sit on 40 or a little above or a little below. Oil pressure does raise when you give it fuel but at a steady 3500 (afraid to rev any higher untuned) I got about 45. What would cause this? It does occasionally have the twitch of a pinched O ring but at a steady 2k the oil pressure is steady 40. Only thing changed was a Torquer 2 cam installed, LS2 chain, and a low mileage LS6 pump (65k and always held 60psi cold and 40 hot in the other motor). Another thing is the car was up on jackstands and I only had 5 quarts of oil in the motor. It seemed to raise a little after I sit it on the ground but I can't see being 1/2 quart low cause lower cold start oil pressure. I'm torn between the O ring, maybe I damaged the OPSU, or hopefully not spun a cam bearing. What do you guys think? This is driving me crazy thinking about it.
Forgot to mention I had the heads and intake off and replaced the lifters. Thats why I was even around the OPSU. I noticed the brake booster hose had been laying on top of it because the wire was laid over like something had been laying on it.

brett walker

iTrader: (6)

Does the motor make any funny noises?

VandykeT/A

Nope, no weird noises.

Whiteaw57

iTrader: (2)

id chage the sending unit first. a buddy of mine snapped his off once when he was changing his intake

bww3588

iTrader: (49)

your talking about a 5-10 psi drop in oil pressure roughly. (stock gauges are not all that accurate). remember this, not all cams are ground exactly alike. the camshaft you installed could be .001 smaller than the stock cam. causing larger oil clearance, and lower oil pressure. also, you could have nicked or scarred a cam bearing on the way in or out.

your oil pressure does not sound like an o-ring issue, generally its low 20's when the o-ring is pinched.

If it were my engine, I wouldnt worry about it. your oil pressure is still very good.

if you are still losing sleep over it, throw a mechanical gauge on it before you go throwing parts at it. see what it is really doing. if it is infact at 40ish at hot idle, go to bed and catch up on sleep.

brett walker

iTrader: (6)

This was going to be my next post. That was the reason and asking if it was making any noise. Its more than likely just the clearance difference in the camshaft.

dodson55

iTrader: (18)

im guessing a torn or wrong o ring on the oil pump but i have also seen cracked sending units read low oil pressure and not leak oil i would start with the sending unit and hope it fixes the problem if it dont pull the oil pump back off and inspect the o ring on the pump

VandykeT/A

I was just worried because I was getting more Oil pressure before I worked on it so I figured I did something wrong. The sending unit is a replacement from advance where I broke it before. How can I hook a mechanical gauge to it?

bww3588

iTrader: (49)

Couple adapter fittings and the oil plug just behind the alternator.

VandykeT/A

Is there anyway to test for the o ring issue? When the car was on jackstands the gauge would fluctuate 3 or so psi until I sat it back on the ground. Then constant 40. It doesn't pick up any pressure with just a slight rev It takes 3k to get the 45ish. Before It kept 55 or higher on a cold start now only 40. That is right around 20 psi. The oil pump that was in the car before held 60psi cold in the other motor and 40 or just alittle over hot.

Whiteaw57

iTrader: (2)

are you using the same sending unit or did you put the replacement one in as you were doing the cam?

VandykeT/A

No, the sending unit was replaced a long time ago when I did my LS6 intake install. I started the car again and it fluctuates psi all the way around now. I assume the o ring is the culprit. I've all ready took the timing cover back off and the O ring is out. I noticed on the new o ring it was actually round. The old o ring is flatened on the sides and is kind of bent I guess you could say. I'm going to put a new o ring in and hopefully it'll fix my problem. It'll at least rule it out but it fluctuated pretty badly. When I first installed the pump there was basically no resistance pushing the pick up tube into the pump.

Whiteaw57

iTrader: (2)

get a good new oring. rub some oil on it so itll slide in. be sure to put it on the tube and not in the pump during install. slide it in straight and youll be golden. good luck, way to take initiative on something youre usure about!

VandykeT/A

The O ring fixed it. With my idle jumping it still moves slightly every now and then but with a little fuel I'm right back up to 55ish. I didn't have it pinched, the sides of were just worn so bad it must not have been able to seal.