Leak source

[kroberts]

I need a second opinion . I appear to have a bonafide leak. It's either my rear main seal or trans input shaft seal. Here is a picture of the leak's exit point. They are two drain holes at the bottom of what would be the "bell housing".



My thinking is that the input shaft seal is leaking. If the rear main was leaking, wouldn't the fluid appear between the engine block and trans? I'm just trying to come up with a battle plan and parts list.

Thanks.

[BDSax]

well, is it motor oil or gear oil? that will answer your question right there. and that is the reason why you change all of that before you put it back in the car.

[StereoInstaller1]

Here is a question for you: Why would you change only one? Seems to me if you were going to go through the hassle of taking it apart, you would change every damn thing in there you could!

[kroberts]

Both are actually new. The engine was rebuilt before I installed it and I installed new seals at both ends of the trans.

[StereoInstaller1]

Both are actually new. The engine was rebuilt before I installed it and I installed new seals at both ends of the trans.

Oh gotcha. Everything shown is really nice and clean, I should have noticed.

Chasing oil leaks under a clean car is a bitch. Oil with 70MPH wind pushing it around can move all over the place. You might want to start off with dye and a blacklight.

[LINUS]

K -

Are you sure it's not migrating from some place you were working & gravity is just making you pull your hair? I had that same thing happpen when I thought I screwed up my valve cover gasket install (don't know how I could have, but I was staring at oil) --turned out it was migrating from my t chain tensioner since the big crush washer was in less than great condition.

Luke's right - if it's worth chasing get some dye & a UV light - if it's motor oil it will be easy to identify since it really glows pink under a light. If you add dye & your leak doesn't glow, you got a tranny leak. I'd do the dye for a quick & easy.

PM me anyhow - I still need to do some comparisons with you over the THR adapter like we planned. I have mine over here now, so maybe we can figure out some stuff.

Are you running (motor) yet there, or is this a non-operating type leak?

[kroberts]

Yeah, my trans looks like shit on the outside. I cant seem to get all amped up about powdercoating and polishing things under my car. The engine is really clean though. I had initially hoped it was my valve cover gasket leaking down the back of the block. I had pulled the VC off last week. I dont think it is.

I think it's my trans. When I replaced the input shaft seal, I accidentally punctured the splash shield behind the input shaft bearing. There is a thin, metal shield inside the gearbox at the input shaft bearing, just behind the seal. When I was removing the old seal, I popped a hole in it. I spoke to a guy at Metric Mechanic about it, he said he didn't think it would be a problem. Evidently he was wrong. Or maybe I dicked up the seal, but I doubt it.

If it is my trans, I'm surprised that it leaked. I've only idled the car in my driveway and driven it up and down my cul-de-sac a couple times. Motor runs fine I guess (I really couldn't tell cuz it's loud as hell with the open header.) I'm afraid to run it with so little back-pressure. My CEL is flashing but that's not really a concern right now. Wiring the THR adapter was a peice of cake. I also used the tach signal PC board that RevEngineer sells here, My M3 dash works just fine. If I ever finish this thing I'm going to get the oil temp gauge working too

I just googled Oil Leak Dye! I wonder if Napa sells a kit. Cool idea. I'm going to try it.

[StereoInstaller1]

If I put oil leak dye in my car, the thing would glow in the dark...