I'm in the middle of a LIM gasket replacement on a '98 Olds 88.

I am using this gasket kit:
FEL-PRO Part # MS958091; 2nd Design; w/Rubber-plastic end seals w/Locating pins; Lower set

It contains two LIM gaskets, two end seals, a tube of Black RTV, and two orange o-rings (called "heater inlet o-rings"; I assume these are the same rings that came on the new coolant elbow I got).

It also conatins one black o-ring, about 13/16" I.D., called "oil filter adapter".
What is this one? Where is it supposed to go? I can't find it in my FSM.

Is this it?

http://www.partsamerica.com/ProductD...pe=102&ptset=A

That'* the kit.

It'* the black o-ring pictured that has me stumped. I didn't see anything like that come out of the engine when I removed the LIM, and I can't find anything like it in the FSM in connection with the LIM.

That could be the O-ring for PCV valve, either the valve itself, or where it seals at the cap Too bad that you didn't buy the aluminum framed gasket from GM.

It'* for my Mother-in-Law'* car. She plans to drive it 2 more years then trade it in or sell it.

When I do my '98 LeSabre, I will be using the GM aluminums.

Finished the job today, and I couldn't find anyplace that o-ring goes, so I didn't use it.

No leaks, car runs great, operational data in spec, and throws no codes...so I guess I'm in the clear.

Maybe that o-ring is only used on a certain year range?

Did you check to make sure your old PCV o-ring isn't in the old UIM?

No, I did not check the PCV valve. I did re-use the old UIM as it was in remarkably good shape (I just replaced the gaskets and installed a Bill Buttermore sleeved stovepipe), and the old PCV.

She'* coming over tomorrow to watch the Bears spank the Colts, so I'll pull her PCV then and check it out.