Need help fast!! In the middle of H/C swap @ 2AM
 

Doing a H/C swap...it's 2AM...

Pulled the old oil pump off, slid new o-ring on pickup, put on new pump, but pickup tube (with new o-ring installed) will not sit flush with the bottom of the pump.

If I put the old o-ring on there, bam, it goes in all the way and sits flush.

New o-ring is blue, old one appears to be brown. New o-ring appears to be more round than the old one.

PNs on both pumps match for LS6 pumps...12556436.

So is my new o-ring the wrong one? Do you think it's for the LS1 pump?

Or is it the right o-ring and I'm just not pushing hard enough to get it to seat correctly?

Need help fast guys...got to get this done.

Thanks.

i have heard that there are two different o-rings. someone else had this problem earlier this week. i'll do a search for it.

Thanks man, let me know what you find out.

I just double checked to make sure, but using the old pump with the new o-ring results in the same thing. Pickup tube will not sit flush with the bottom of the pump.

Apparently somewhere along the way, the people who owned the car before me must have had the oil-pump changed and went with an LS6 pump. I was under the impression that it was bone stock internally.

I'm guessing I've got the wrong o-ring.

Anybody else feel free to chime in...I definitely need the help.

https://ls1tech.com/forums/generation-iii-internal-engine/506248-oil-pump-o-ring.html

read this thread.

The blue oring for sure works on the Ls6 because I have it and used it....Be certain you dont pinch that baby lube it up a little. ;)

What is the color of old ring?
The new one will not be compressed so it will be thicker to start with, just center it and bolt it on. Check the back of pump if it is not pinched.