My 89 GXL rex has a bad oil leak. The oil comes from behind the OMP, in the cravasse between that and the exhaust manifold. I am not sure of the source, however, as it is very difficult to see back there (only way is with my car on ramps, and me underneath..and this still sucks). She loses quite a bit of oil...especailly when revved up. I do not think it is the OMP itself. Is it possible that the Oil Pump itself blew an O-Ring or something, and the oil is leaking through the front cover? Nothing special happened to make her start leaking, I had done no recent work on the car or anything. The last oil change was about 1500 miles before it happened, and I did another one since to replenish the oil supply (and to get 10w30 in there for winter, although at present I never really run her).

Any ideas on what could be leaking? Any common problems like this? I'm really not sure what to check next.

 

OMP lines? These get brittle with age...perhaps it's your front cover? Take your fan shroud and air pump off and degrease this whole area and get it clean. Then run the engine and pinpoint the location...it shouldn't be too hard.

 

I know it's not the lines...they're clean. I can see it leask in behind the OMP...I guess this weekend or something I'll give that degreasing thing a shot. Any other ideas? Can the front cover itself just leak, or does it mean that an O-Ring is gone in there or something?

 

I had a leak from the front cover on my 91. It leaked at about the 1 o'clock position, just to the cinside of the crank position sensor. Never did figure out why.

I replaced the gasket with the engine in the car, which is fine as long as you make a fairly clean break on the oil pan gasket. It's a fairly straightforward pull and replace procedure, but the bolts (6 or 8, I think) that secure the front cover to the oil pan can be a real pain to get to. Now would be a good time to drain your oil and inspect the pan and pump pickup for gunk. When installing the new gasket, use some RTV in the corners , and possibly some around the centerline of the oil pan gasket and to the inside of the bolt holes.

There is also a o-ring that seals the OMP to the front cover. It is possible that it has failed.

Ren

 

Chances are it's your OMP

If it is comming from the back then either the main "O" ring for the OMP is leaking or the back plate on the OMP is leaking. Mine was. The back plate is held on with two phillips head screws, behind it is a small "O" ring almost oval in shape about the size of a dime. It's an easy fix, use some "forma gasket" to seal the end plate, and buy a new "O" ring for the main pump it's only a couple bucks. Be carefull not to over tighten the bolts on the OMP or you'll do what I did SNAP!

If this does not solve the problem then the leak may also be comming from the shaft of the OMP lever that goes to the throttle, in this case you should see oil comming out of the screw on the end of the shaft.

If none of this solves the problem than there might be a leak from the front cover which is kind of a pain in the ***, but try the OMP first it's probaly your best bet.

 

Yeah, been there already, heh. Bottom bolt snapped on me (manual says 8 lb-ft of torque to tighten if I remember right). Luckily in about 45 minutes i was able to gator-clamp-untighten what little bit of the bolt was left in there. I also already replaced that main O-Ring. I'll check out the seal with the end plate, I hope that's the problem (easy and cheap to fix). Thanks a lot.

 

Turned out to be the front cover. Ran me upward of $600 to get it fixed, but hey, that's the way it goes sometimes. Unfortunately, the mechanics who fixed it gave me another problem -- my engine SHAKES like crazy, even at idle. I'm going to try and figure out what's going on with that, now. Thanks for the suggestions on the oil leak everyone, it's nice to know at least that isnt a problem anymore.

 

sound like a blown passanger side motor mount these fail often,,,,

 

Car is back to normal. Refer to this link for the dirt.

Eric