ryle

iTrader: (19)

I just finished my H/C/I swap and fired up my engine. At first the oil pressure looked great @ ~50 PSI. I took the car for a test drive and the pressure dropped to ~30 @ 3k rpm and at idle it was closer to 20psi. I installed a melling High Pressure pump so I would assume the pressure should around 50-60 psi at 3k. I talked with my machinist and he said it most likely is a leak somwhere. I also installed a double roller Timing chain so there are spacers between the pump and block. any ideas?

09camaro383

iTrader: (2)

most likely a pinch o-ring on the oil pump!! my car has a HV pump and a double timing chain and my pressure is always in the 165+

kliped

iTrader: (2)

your oil pressure is at 165psi?!?!?! i dont know to much about ls1s yet but that oil pressure seems insanely high

aTeam

I think he means 65+

ryle

iTrader: (19)

well, I plan on taking the timing cover off and inspecting the o-ring as well as making sure I didn't get any junk between the pump, spacers and the block.

It just seemed odd to me that I would have good oil pressure upon startup and then the pressure would drop like that. I let the engine cool and restarted it and it was sitting at 40 psi.

Slvr00Bird

iTrader: (2)

Pull everything back apart and look at the pick-up tube O-ring. Did you buy a new O-ring or re-use the stocker?

ryle

iTrader: (19)

brand new o-ring that came with the pump... Had a hell of a time getting the pickup into the pump. hopefully that's all that it is, but I still don't think that explains why I had 50 psi initially upon startup. I would think if it was an oring it would have been screwed from the beginning.

09camaro383

iTrader: (2)

type error i meant 65+. ryle when you install a HV pump and double timing chain the hole on pick up tube leg doesn't align any more with the stud I had to make the hole longer! you probably pry that sucker in and damage the o-ring!!

1SLwLS1

iTrader: (6)

stock block?

justinj

iTrader: (2)

Must be a O-ring.. or if you were rough on the pick up tube when installing. You could have made a hole at the weld were it connects to the block. Do the O-ring first, droping the oil pan is no fun. Just another thought cam plate?
Could be so much stuff.

Has anyone ever installed 2 O-rings? Just wondering if it would work the same.

ELDIABLO

iTrader: (28)

Yeah more than likely it is the o-ring...when you install a double chain and shim the oil pump it puts your pick up tube at a different angle and the pick up tube wont bolt up to the wingate(spelling?) tray like it did before....I would just bend the tube mount to fit the wingate tray and make sure the o-ring isn't pinched.

ryle

iTrader: (19)

Yes, block is stock with 150k on the clock

1SLwLS1

iTrader: (6)

Check the pickup tube o-ring for sure then.

ryle

iTrader: (19)

well, I pulled the timing cover and pump last night and didn't find any problem with the O-ring. I am hoping that I just got some junk in between the oil pump, spacers and block. I cleaned up the mating surfaces and put very light film of prematex 2 on both sides of the spacers hoping that might help seal it better. I'm gonna finish bolting up the timing cover and oil pan tonight and keep my fingers crossed.

1SLwLS1

iTrader: (6)

Before you go that far, did you replace the cam retainer plate when you did your swap? That has a small gasket that is easily crushed from over torquing the bolts and would cause a low pressure system.

sscamaroburn02

iTrader: (14)

yeah sounds like you may have just installed the oring incorrect. i re-used mine with 73k and it works just fine. let us know what happens tonight.

ryle

iTrader: (19)

I saw the gasket on the plate but I did not replace it. I will recheck the torque while it's open. it could be overtorqued...

1SLwLS1

iTrader: (6)

I replaced mine when I originally did my cam swap 3000-4000 miles ago. I followed the torque specs. When I tore my engine down just recently and attempted to transfer parts to the 408 block, it needed a new one. It was like $15 max. Seems as if they are 1 time use deals. Super easy to crush. I would rather spend the $15 when I am taking that on/off just for ease of mind for situations similar to yours. My 408 had low warm oil pressure and it could point to only the o-ring or pump considering that was replaced. Mine ended up being the wrong o-ring, the thicker truck version, red.

http://ls1howto.com/index.php?category=1 Put this link in your favorites. It has most of the torque specs. 18 lb-ft. for the cam retainer bolts, qty (4).

ryle

iTrader: (19)

WTF!?!? I checked the O-ring, spacers, and cam retainer plate. I put everthing together and buttoned the whole thing up, started the engine and had great oil pressure when I first started it up, even higher than last time with 50psi @ idle. I'm thinking I'm set so I take it for a test drive. at the beginning it reached 70 @ around 3500 rpm. Unfortunately, Slowly but surely the pressure started dropping. Just like last time after about 15-20 minutes the pressure dropped to 20psi at idle and would only reach about 38psi when I gave it a little gas.

1SLwLS1

iTrader: (6)

Do you have the high pressure spring or low pressure in the Melling pump? Shouldn't matter as either spring will not affect idle. You said this was the stock block, right? Hmmm...the gasket was good on the retainer plate?