Yep. Crank seal and oil pump drive sleeve #3 on the 944 n/a. I seriously thought I had it nipped in the bud this time. Finished the install the other night, took it for a test drive (about 25 miles) and checked underneath - no leaks. Sweet.

Today, looked under there and I've got that brownish-yellow drip line right down the front of the oil pan from the crank main seal. ****ing bloody hell. What is it with these things? This install was absolutely clean and by-the-book. Are these seals THAT bad?

Maybe it'll go away, or maybe it's just some residual dripping down from elsewhere (although I cleaned everything on the front of the engine when it was apart).

What the heck is the deal with these? Are they always this bad? My 951 doesn't leak a drop (at least not from there. . .)

 

question #1

did you replace the sleeve on the third seal? The sleeve may have a nice groove worn in it that make the seal leak.

#2- did you oil up the seal when you put it in or did you install it dry and its burning the seal up rapidly?

#3- could you NOT press the seal in completely to get it to ride on a different point on the sleeve?

#4- how are you installing the seal? with a large socket, w/a hammer tapping around the edge, or with a razor blade? ok not funny but.......could the housing be gauged up and leaking around the outside of the seal and it needs some rtv around the seal before you install ONLY if you have a messed up housing.

 

Dan beat me to it, I can't really add to this other than...

did you replace the O-ring on the front of the sleeve? That could be an issue as well.

I'm still throwing a vote for the sleeve having a groove worn into it.

 

Well, this time I installed both the new sleeve and seal at the same time - cleaned up the groove in the oil pump real good where the seal sits and tapped it in by using a big socket (1-1/2" IIRC) and hammer - that way there was no uneven-ness to the seal getting pushed in one side first then the other or anything like that. I sprayed a little WD-40 on it to get it to slide in better and wiped everything down good once it was seated, then used some Yamabond-4 on the outer edge of the seal just in case. My only thought can be it's at the junction of the drive sleeve and inside edge of the seal. I just can't believe what a pain in the *** this is. Third friggin' seal and second drive sleeve. Guess I'm out another $60 and another weekend to do it AGAIN.

 

DON'T use WD-40 on your seals. That crap eats them up, trust me .
When I install seals I either use motor oil or silicone grease it is less harsh on rubber, viton, or plastic seals.

 

Are ya SURE its the crankshaft seal? And not an oil cooler/plug gasket bleeding into the belt covers, or a trail down from balance or camshaft seal, or even from the mating surface of the oil pump? Are you SURE your getting and using the correct seals there?

3 times? Still leaks. Makes one wonder.

However....your statement "I sprayed a little WD-40 on it to get it to slide in better and wiped everything down good once it was seated, then used some Yamabond-4 on the outer edge of the seal just in case". Makes me wonder about just how this process is really being done. Yamabond on the outside of seal diameter, after install? Whats that gonna do? Maybe if it was on there when seal was driven in it might, but not after the fact. No expert here, just an observation. 3rd time SHOULD BE a charm.....not true here, obviously. Good luck!

 

"DON'T use WD-40 on your seals. That crap eats them up, trust me .
When I install seals I either use motor oil or silicone grease it is less harsh on rubber, viton, or plastic seals."

I have to kinda agree! I don't like this crap. Very little applications in automotive (if ya ask me, much more gooder chemicals to use than this stuff). If your trying to get yamabond to stick to anything after using this on it, without a REAL good cleaning process first, your dreaming.

 

yeah could be the housing leaking - which just tightens to the block w/ a very thin layer of block seal on there. Just did my whole motor and no leaks yet.....I would suggest a pressure wash cleaning and then run it and seee where its leaking w/ the belt covers off..

 

Jeff, you might remember that I recently reported that my front seal was leaking and had actually blown out of its seat and when pushed back in it would spin with the crank. I tore apart the front of the engine and found the sleeve in perfect condition but the seal was a loose fit. A new seal is tight. I was just gonna button it back up, but then started to suspect excessive blow-by under boost might be pressurizing the crankcase and forcing oil out this seal. So, I'm digging deeper now. When it comes to installing the seal, I would use a little motor oil on the inside edge of the seal (where the crank rides) and keep the outside edge and pocket completely dry or maybe Yamabond/Loctite538. These seals don't fit tight enough to need a lubricant to install them.

Anyway, is it possible that your root-cause is blow-by ? Is your rear main seal also weeping oil ? Is there lots of oil in your intake system ?

 

Why are you yamabonding it? I typically will use a little AT fluid (whatever I have sitting around, any clean dino oil works fine) to help lubricate it while its going together, and that it. As long as there are no obvious scars on the surfaces, it should seal fine.

Regards,

 

Grease also works well.

I use ATF for the injector seals, engine oil for the engine seals....basically i follow whatever the manual mentions.

 

Thanks for the help - I'll try to explain the install. I'm 99.9% sure the seal I used is the correct one - I cross-checked the part # with the PET and yes, it was a VERY snug fit. The new drive sleeve had (obviously) no groove worn it it and the little beveled o-ring was installed like it should have been.

The WD-40 was only used on the INSIDE of the seal to help the drive sleeve slide into it as it and the drive sleeve were being pushed into place. And I used it very sparingly. Once the seal and the shaft were seated I smeared a little (very little) Yamabond around the outside edge of the seals - the face if you will, but only towards the outside. This way I'm absolutely certain that if the seal is leaking, it's leaking from the INSIDE of it - where the drive sleeve is. It's just insurance - nothing more. I don't glop it on (a little goes a long way) and none was applied to either the seal or the front part of the oil pump assembly where the seal goes PRIOR to the seal going in - and I'm certain everything was clean and dry (let it sit for a couple days prior to putting the Yamabond on. I actually took some pictures; I'll upload them in a little while. The upside is I'm getting rather good at this job and it's getting faster each time. . . The downside is I REALLY want zero leaks and I'm "this close" to attaining that goal. It's one of the last little mechanical gremlins I'm exorcising from this car prior to bolting on the Callaway stuff.

Well, that and I noticed the pass. side A-arm bushings are shot while I was under there. . . Guess that's two.

 

Look for any scratches on the shaft. Roughness will just eat the seal up. Look at the removed one to see it that's the case. Some emery cloth might be needed there. Easy to scratch when removing the old seal.

I use redline assembly lube on the shaft and seal inside when assembling. One PITA hting is when the little spring comes off. Gotta put it on very carefully. I'll use an awl to nurse it around the shaft.

I've never seen a seal that leaked around the outside. Using a sealant there just sounds like trouble especially for any (inevitable) removal and re-installation. Gotta clean it off as it might come loose in chunks leding to leaks.

 

I have seen a seal leak from the outside and rotated with the shaft. It turned out to be the wrong part. Now I always double check the part number on the original seal against the new one. Get a second set of eyes on the job while you are doing it next time and may help you notice something you are not noticing previously.

 

I'm pretty certain the seal is correct (I cross-checked it with the PET # a while ago) but I'll double-check it again and post the part # when I get home later. This job is pretty simple, it's just annoying as heck to do it three times.

Oh well. Off to Pelican to order another sleeve and seal. . . Grumble, grumble, grumble

At least I got the oil changed and the belts retensioned I suppose. Car is running awesome and the leak isn't that bad, but any leak is too much as far as I'm concerned - especially with new parts installed and ESPECIALLY on an engine I'm planning on pushing more power out of by turbo-ing.