Help oil pressure issue!!!
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Teching In
Joined: Oct 2017
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From: From the 405
Help oil pressure issue!!! I've been working on my ls1 3 weeks now. I changed heads from a set of 862 heads that I had lying around at the time to a set of 799 heads. Prior too changing out I have great oil pressure. Idle when warm was 40 psi cruising was 50-60 and wot was 70 -80 psi. After changing heads I drove about 40 miles to my house and oil pressure dropped to about 15 lbs. Changed oil pumps thinking stuck valve was issue and it had no fix. Ran a thicker oil and changed filters still no fix. Am currently running a melling 10295 hv/hp pump and am still getting 15 maybe 20 psi at idle when causing it's still about 20 and I'm afraid to open it up any. All seals are good and freshly changed and there is no metal in my oil whatsoever. Any advice would be awesome!!!
i would actually pull the sending unit and install a temporary mechanical gauge and verify you do or don’t have good oil pressure. The above poster might be correct in stating it’s the sending unit (the factory gauge is just a rough guesstimate anyways) but if it’s not the sending unit you’re still going to be questioning about your pressure.
I also vote trying the sending unit. Swapping heads only shouldn't affect oil pressure.
Did you get any further into the engine or ONLY swap heads?
I had a similar issue to yours after I accidentally broke my original sender and a buddy gave me a used one, the used one read about 20 pounds lower and my gauge would sometimes bounce at low rpm. All I had changed was the intake manifold and the sender.
Did you get any further into the engine or ONLY swap heads?
I had a similar issue to yours after I accidentally broke my original sender and a buddy gave me a used one, the used one read about 20 pounds lower and my gauge would sometimes bounce at low rpm. All I had changed was the intake manifold and the sender.
Thread Starter
Teching In
Joined: Oct 2017
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From: From the 405
We change out sending units with another unit and it still reads low after the truck is warmed up. Had some guys at a trusted shop look at it for a couple hours and they all agree it is more that likely a spun cam bearing it was just coincidental that it happened after changing out the heads mechanical guage drops pressure just like the sending units both did.
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From: Ohio
I've been working on my ls1 3 weeks now. I changed heads from a set of 862 heads that I had lying around at the time to a set of 799 heads. Prior too changing out I have great oil pressure. Idle when warm was 40 psi cruising was 50-60 and wot was 70 -80 psi. After changing heads I drove about 40 miles to my house and oil pressure dropped to about 15 lbs. Changed oil pumps thinking stuck valve was issue and it had no fix. Ran a thicker oil and changed filters still no fix. Am currently running a melling 10295 hv/hp pump and am still getting 15 maybe 20 psi at idle when causing it's still about 20 and I'm afraid to open it up any. All seals are good and freshly changed and there is no metal in my oil whatsoever. Any advice would be awesome!!!
What did you do about head gaskets during the swap?
