Low oil pressure problem with an lq4
Thread Starter
Teching In
Joined: Mar 2010
Posts: 3
Likes: 0
Low oil pressure problem with an lq4 I have done pretty thorough search, and I still can't find a fix for my problem.
I bought a stock lq4 from the salvage yard, did a cam swap, and put a carbed intake on it and put it in my truck.
When I start the truck, it takes about 30 seconds for it to get oil pressure. After that it will hold 30-35 psi at idle, but it does not go up with rpm. Once it finally gets pressure, it does not knock or rattle any at all.
Heres a list of what I have checked and replaced.
New pump o-ring. TWICE <I have read about the green and black ones, the one I bought at GM was red. I have also read about how hard these are to put in, mine slid in without much trouble. It did have to compress a little to fit in the pump but not much. Its definately not wedged in tight. I double checked with the GM dealer and he claims I have the right one.
New ported/shimmed late model pump.
New cam retainer plate/seal.
Check plug under timing cover for leaks.
New oil/filter. Tried both Mobile 5w30 and Valvoline 20w-50. Using Napa Gold filters both times.
Tried 2 different oil pressure gauges, the one I am using reads about 5psi more than the 2nd gauge.
Tried taking oil pressure reading from 2 different places.
So, I am at a loss. I would think if it was loose internal clearances, it would have lower oil pressure at idle and I would think it would still go up with rpm.
Does anyone have any ideas of what else I can check?
Thanks
Lynn
I bought a stock lq4 from the salvage yard, did a cam swap, and put a carbed intake on it and put it in my truck.
When I start the truck, it takes about 30 seconds for it to get oil pressure. After that it will hold 30-35 psi at idle, but it does not go up with rpm. Once it finally gets pressure, it does not knock or rattle any at all.
Heres a list of what I have checked and replaced.
New pump o-ring. TWICE <I have read about the green and black ones, the one I bought at GM was red. I have also read about how hard these are to put in, mine slid in without much trouble. It did have to compress a little to fit in the pump but not much. Its definately not wedged in tight. I double checked with the GM dealer and he claims I have the right one.
New ported/shimmed late model pump.
New cam retainer plate/seal.
Check plug under timing cover for leaks.
New oil/filter. Tried both Mobile 5w30 and Valvoline 20w-50. Using Napa Gold filters both times.
Tried 2 different oil pressure gauges, the one I am using reads about 5psi more than the 2nd gauge.
Tried taking oil pressure reading from 2 different places.
So, I am at a loss. I would think if it was loose internal clearances, it would have lower oil pressure at idle and I would think it would still go up with rpm.
Does anyone have any ideas of what else I can check?
Thanks
Lynn
Thread Starter
Teching In
Joined: Mar 2010
Posts: 3
Likes: 0
I found out the problem. I made a plate to block off the oil passages on the drivers side of the pan. I didn't know the oil had to go out one hole and back in the other.
Now it holds 60 psi cold and about 80 cold at about 3000 rpm.
Lyn
Now it holds 60 psi cold and about 80 cold at about 3000 rpm.
Lyn
