I will start off with this. I have a 01 Z06. Have owned it for 7 months and installed all the basic bolt ons. Always had about 60PSI of oil pressure. Well this week I decided to do a cam swap. I dropped the front sub frame so the pulley could be removed. Did all the necessary procedures..(blah blah blah) I did remove the pickup tube on the oil pump to replace the timing chain. I was VERY careful putting the tube back on b/c of the dreaded o-ring. I would almost bet my life on it, that its NOT pinched.

Obviously I put everything back together and did the initial start up. 15 PSI oil pressure. On rev up it goes to 30-35 PSI MAX. Car definitly doesnt have any valvetrain noise or knocking what-so-ever. Figured I would change the oil thinking that maybe some coolant ran into the oil pan while the timing cover was off. So now, I have the rear jacked up higher than the front to let all oil drain from the pan, since the plugs on the front. I went with a 20w50 and a new filter just to see. So I start the car up again. NO OIL PRESSURE NOW... IMMEDIATLY shut the car down after 3-5 seconds.

So now I am thinking that all along it was b/c the car was jacked up in the front originally and jacked up in the rear on the second start up after the new oil change. Now I think I have the answer, so I lower the car down all excited. Get all 4 wheels on the ground, start it up, and it jumps to 15-20 PSI within 2 seconds. Not what I wanted to see, but obviously better than the 0 PSI.

What the hell is going on here? When the subframe was dropped down a couple inches, I did jack up on the oil pan to make the pulley clear the power steering rack. Could I have messed up the pickup somehow? The motor was smashed against the 'firewall'(if you wanna call it that..LOL). I checked the pressure sensor behind the intake thinking that maybe it was the problem but its not broke or anything. I am going to put a manual gauge on it tomorrow to find out for sure but in the mean time, Please help me out here. I am going crazy. I am about to pull the damn motor at this point.

 

No matter what you think you either pinched/cut the o-ring or the tube didn't seat on there straight, do not bet your life on it please. Trust me, if you had good pressure before that's the only thing it could be. Traver

 

Buy a new O ring, try it again. The only other issue is the pickup height may have changed? If it is too low, the oil pressure will be a mystery.

 

I am 99.9% sure it is that o-ring. I just put my LSX 427 together and was also very careful with the o-ring installing the pickup tube and when I went to start the engine I couldn't get any oil pressure. I took the pan back off, took the pickup tube off, everything looked good. I reinstalled the o-ring and pickup tube. I got oil pressure very quickly and I have 65 psi oil pressure at idle now.

 

I install the o-ring with the cover and gears of the oil pump removed so I can see for certain if the o-ring seats correctly.

 

my first Ls1 rebuild I had this problem, So ever sense I use a little hi temp rtv around the pickup along with the o ring, but keep the rtv below the o ring so that none of it gose between the pump and the o ring. So far its worked great on all the engines I have done!!

 

Alright... Here we go...LOL..

Well first off, I want to thank all you guys for helping me out. Anyways, I started the car when I got home from work yesterday to check oil pressure again just to make sure before I tore it down AGAIN. Well I switched the gauges to the digital, it took about 1-2 seconds to read pressure but then SLOWLY raised. I could probably count to 30 faster than the pressure reached to 30PSI. I know its not supposed to be like that, so I went to the first and easiest thing.

I removed the intake, pulled the fuel pump fuse and unplugged the coils. Hooked a mechanical guage up. No oil pressure at all when cranking for 10-15 seconds. Well, obviously somethings wrong, so went ahead and did all the work to get the balancer off and all the other stuff. Finally got to the oil pump now. Removed the o-ring. Looked good(but you cant go by that), so we messed around with it, tryed a few different ways, and still no oil pressure. My dad was watching the oil pressure while I was turning the car over. There was no oil whatsoever getting slung around by the oil pump. I still have the timing cover off so the chain and pump are visible, which leads to my first question.

Should the pump sling oil everywhere when its being cranked over continually? The oil pump isnt even getting oil on itself. I would think that it should go everywhere but maybe not. Im not too familliar with the LSX setup.

This is basically where I left off for the night because I am stumped. I guess I could try a new oil pump but I would hate to buy the pump and it not be the problem. Let me know what you opinions are.

 

did you purchase and install a new o-ring or just mess with the old one?

 

The pump is going to suck oil out of the oil pan with the pickup tube, through the pump, and send it to the oil filter, and out of the filter through the engine. So the pump is not going to sling oil everywhere. You have no way of just watching the pump to know if it is working. If you leave the oil filter empty and crank the engine over, then take the filter off and if there is oil in the filter then the pump is pumping.

 

No, I messed with the old one, but I am heading to the local chevy dealer now to grab a new o-ring and oil pump. I am going to try the new o-ring first, if that doesnt solve it, then I am going to put the new pump on too. If the 2 of those dont solve the problem, then the motors comming out and nothing stock is going back in...but I dont want to go that route right now.

 

Well we are cranking the engine over with the mechanical gauge on it and neither the car nor the mechanical gauge is registering any pressure.

This might be a stupid question but, I dont have the intake or any of the front of the motor parts on the car(ex. water pump, timing cover ect....) The car should still get oil pressure even though all thats off right?

 

Yes it should.