Low Oil Pressure after H/C/I swap
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Low Oil Pressure after H/C/I swap
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?
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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.
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.
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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.
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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!!
Last edited by 09camaro383; 07-25-2010 at 11:25 PM.
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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.
Could be so much stuff.
Has anyone ever installed 2 O-rings? Just wondering if it would work the same.
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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.
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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.
#15
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.
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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).
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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.
#20
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?