Low oil pressure.. help..
03-25-2007, 08:00 PM
#1
Low oil pressure.. help.. Need some ideas here..
Ok, here's the deal. New LS2 engine that was dyno tested outside the car and had great (high) oil pressure.
When we installed it in my '68 Camaro we needed to swap from the LS2 (vette) oil pan to an F-body LS1 pan for clearance. We swapped on the f-body oil pan, tray and pick-up. Oh, and an LS1 dipstick.
Now when we fire up the car we only get 10psi at idle and barely more (less than 20psi) when we up the RPMs.
Ideas?
My first thought was that we forgot (or it fell off) the O-ring on the pickup where it goes into the oil pump. I have a hard time believing the oil pump suddenly went bad.
Also, I'm taking an electronic oil pressure reading off the fitting above the oil fitting and I made a fitting to mount a mechanical gauge in the place where a factory car gets it's oil pressure reading (right behind the intake manifold). We also tried two different mech gauges to make sure the reading was right.
Ideas on what to check?
Right now I'm going to pull the front timing cover and check o-ring. What else could it be?
Trying to get the Camaro done by Thrusday so any help would be appreciated!
Thanks
Ok, here's the deal. New LS2 engine that was dyno tested outside the car and had great (high) oil pressure.
When we installed it in my '68 Camaro we needed to swap from the LS2 (vette) oil pan to an F-body LS1 pan for clearance. We swapped on the f-body oil pan, tray and pick-up. Oh, and an LS1 dipstick.
Now when we fire up the car we only get 10psi at idle and barely more (less than 20psi) when we up the RPMs.
Ideas?
My first thought was that we forgot (or it fell off) the O-ring on the pickup where it goes into the oil pump. I have a hard time believing the oil pump suddenly went bad.
Also, I'm taking an electronic oil pressure reading off the fitting above the oil fitting and I made a fitting to mount a mechanical gauge in the place where a factory car gets it's oil pressure reading (right behind the intake manifold). We also tried two different mech gauges to make sure the reading was right.
Ideas on what to check?
Right now I'm going to pull the front timing cover and check o-ring. What else could it be?
Trying to get the Camaro done by Thrusday so any help would be appreciated!
Thanks
Last edited by Steve1969LS1; 03-25-2007 at 08:12 PM.
03-25-2007, 08:30 PM
#4
On The Tree
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There is a dumb-bell shaped oil galley plug in the rear of the block underneath the rear cover. The machine shop failed to put that back in when they gave the block back to me and I failed to realize it. That gave me the same problem you have, 10 psi at idle and ~20 psi at revs......Just a thought.
~Paul
~Paul
03-25-2007, 08:42 PM
#5
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did you have to change the oil pressure sending unit for any reason? i know those are picky, especially if not screwed in all the way. only other reason i can think of would be not having the proper clearance between the pickup and pan. hardrock has a good theory as well.
Last edited by ProjecT 9; 03-25-2007 at 08:51 PM.
03-25-2007, 08:51 PM
#6
Originally Posted by ProjecT 9
did you have to change the oil pressure sending unit for any reason? i know those are picky, especially if not screwed in all the way. only other reason i can think of would be not having the proper clearance on the pickup and pan. hardrock has a good theory as well.
Thanks to Hardrock for the other idea. I don't think Westech would have pulled that plug for any reason. All we did was slide in a cam and swap the intake/heads.. Oil pressure at Wetech was very good.
Keep the ideas coming.. doesn't this sound like the "forgot the o-ring" sort of problem?
03-25-2007, 09:01 PM
#7
LSxGuy widda 9sec Mustang
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Sounds like o-ring to me. Was everything new, or was this a reused o-ring? You have to be extremely careful with that o-ring. I use red engine assembly lube in the pump, and on the o-ring and I'm still paranoid when installing pickup tubes.
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03-26-2007, 07:40 AM
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Originally Posted by -Joseph-
Sounds like o-ring to me. Was everything new, or was this a reused o-ring? You have to be extremely careful with that o-ring. I use red engine assembly lube in the pump, and on the o-ring and I'm still paranoid when installing pickup tubes.
03-29-2007, 05:49 PM
#9
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having the 1/4" clearance from the bottom of the oil pan to the pickup tube is very important. If you don't have enough room to draw oil from the pan you will starve the oil pump. It's very common for the clearance to be wrong. I use modeling clay to check the height or you can braze a couple of 1/4" tabs to the end of the pickup to guaranty the 1/4" clearance.
