Oil Leak behind flywheel

[dc914guy]

Hello All~
What is involved in replacing the main seal behind the flywheel? What parts do I need and how much am I looking at?

I figured I would address this now rather than later.

~Eric

[Dave at Pelican Parts]

CV joint gaskets, because you will be removing the transmission.
Muffler gaskets, because you will be removing the muffler so you can drop the transmission.
Heat exchanger gaskets and nuts, because you may want to remove the exchangers to drop the transmission.
The seal.
A new flywheel "lock plate".

...I think that's all that is absolutely needed. I would consider replacing the clutch disk, since the tranny will be off the motor anyway. Ditto the bushing in the clutch throwout fork and the throwout bearing. And also the bushings in the shift linkage, as you will have (the rear half of) that apart anyway.

...Then we start getting seriously into "Dirk Wright's Disease", also known as "While You're In There..."

--DD

[Va914]

Ditto on Daves response and if your ordering seals and stuff from P Parts......you may as order the Tranny main seal. It's cheap and you may find a leak (Like I did) from the tranny seal too.

Best of luck
Kerry

[3D914]

Since misery loves company,

You might as well order the front main seal as well (since its probly just as old), pull the whole engine out and do them both. Easy weekend job.

Ask me how I know!

[Dave at Pelican Parts]

The front main seal can be replaced with the engine in the car. You don't want to, but it is possible. I think even someone with four elbows per arm would think the task "moderately annoying", and for those of us who make do with only one per, I think "just barely possible" covers it pretty well.

--DD

[tryan]

the cam galley plugs behind the flywheel can leak also, but not a weekend job.

plastic cup on the clutch arm. yah. you just never know.

[74914]

I'm in the middle of a clutch job and suggest in addition that you check the condition of the flywheel pilot bearing, flywheel o-ring, and felt washer. Mine were either trashed or disintegrated.
Tryan; I didn't know to check the oil galley plugs but don't recall seeing any oil weeping from anywhere other than the mail seal. Would that leak just under pressure, or would I have noticed after I cleaned up the area behind the flywheel? I just bolted up the flywheel/pp/clutch tonight but could remove them and do some checks.
Thanks
Ed

[jamcleod]

you can re: and re: the trans with the engine in. it's possible to do the seal alone or, depending on how much you want to do, follow the wise advice given above.

[BenI]

Parts list to buy from Pelican:

Main seal ... about $10
flywheel bolts ... about $10
felt washer ... <$1
flywheel o-ring ... $1
flywheel crush washer ... $1
needle bearing in flywheel ... $3
CV gaskets x2

CRC Brakeleen brake parts cleaner (local parts store has this spray can) - this is great for restoring an oily driven disk. You spray it on and it disolves the oil and evaporates. If there's just a little oil on the clutch parts this will save you some money. You also probably want to get some sandpaper to go over the flywheel and pressure plate surfaces after you clean the oil off them.


Tools: Pelican sells these too
Flywheel lock tool
Clutch centering tool
12-point tool for removing CV bolts





You can do this job without removing the tranny but it's just not worth it. Remember to disconnect the battery and remove the starter-this will make the tranny more balanced and easier to handle. While youre in there you may want to peen the metal around the three oil gallery plugs, or tap them and replace with 3/8" NPT plugs. You will risk getting metal shavings into the case though. Also, you may want to buy new stainless hardware for the muffler to heat exchanger mounts. Good luck-the first time I did this job it took 6 hours-now I can do it in about 2. I had a severe leak that I blamed on the main seal but after 4 seals had to face the fact that my main bearing was shot. I am not at all suggesting this is your problem-just letting you know I'm way too familiar with this job.

[Dave at Pelican Parts]

Forgot about the tools...

As an alternate to peening the case or pulling the gallery plugs, you can clean them carefully and then put some epoxy over them. Not as secure, but certainly better than nothing.

--DD

[Jake Raby]

ensure that the flywheel does not have a groove in its surface from the old main seal.....If the surface is grooved, no seal will ever repair the problem. I have atleast 20 flywheels like this that are now junk.

[M. Hendrix]

Since you are doing all that, what's a coat of paint?





M

[Zeke]

I'm glad BenI mentioned the FW bolts. The new multi hole washer is a must, but the bolts need to be tossed as well, IMHO. I had a 911 engine let one of the bolt heads booger up the flywheel and pressure plate about 10,000 miles after a complete rebuild. That was very expensive.

[Andyrew]

When you say oil leak, do you mean something like this? Because this is what mine looks like, What all should I do?



Thanks guys..

[Dave at Pelican Parts]

Pull the flywheel and check behind it. Probably the flywheel seal, maybe something else. Replace what is leaking, and consider doing at least some subset of the other stuff we've been talking about.

--DD

[Jake Raby]

Also, ensure one of the 3 rear galley plugs is not leaking........it may look like a rear seal and not be. Verify!

[dc914guy]

Jake~
Where would the rear galley plug be located?

Thanks,
~Eric

[Jake Raby]

There are 3 of them, 2 in one case half, and 1 in the other....any of the 3 can leak at any time.

[jackmech]

Also while you're there you can check your endplay and swap out shims as necessary. Always have 3 in there, no more, no less.

Mark D.

[dc914guy]

I did remove the three shims, how would I know if they need to be swapped out?

~Eric