Should I clean behind flywheel & Clutch Release bearing torque??

jcsjcs · jcsjcs's Garage

Hey all - Replacing my flywheel and clutch.

Should I clean all the gook behind the flywheel during this process?

If so, what to use?

Also anyone know what the torque spec is on the 3 screws holding on the Clutch Release bearing? Don't see it anywhere....

BGCarrera32 · 07-25-2010, 08:18 AM

I think whether or not you clean the goop out is up to you- I would. Can't hurt to help keep the heat down. A common thing to do depending on mileage/originality is to replace the large crankshaft seal on the engine behind the flywheel. Have you looked to see of maybe it is ever so slowly seeping and that's what created the "goop"? If you have not done one before or are not comfortable doing so get help from someone that knows 911s. They have to be replaced and seated carefully.

Whatever you do, DO NOT clean out your throwout bearing with brake clean or similar. You will flush the grease out of it and they are not repackable. Then you have to replace it or try and bring it back to life with Wurth HHS-2000.

Not sure on the screws. I know what you are referring to but don't recall the value...

jcsjcs · jcsjcs's Garage

Funny you should mention the seal - I actually just removed the old one and am a bit stumped as to how to get the new one in without the "special" tools.

No one around who has one done before so any direction is appreciated.

I will also do a search.

Does not appear that the old one was leaking - but it was a bit brittle when I removed.

BGCarrera32 · 07-25-2010, 09:19 AM

Basically, I like to use something round that will sit over the outer perimeter of the seal- I'm talking about the rigid overmolded steel edge. This will allow you to start gently tapping it into place with a rubber mallet or similar, I don't like tapping on the seal edge directly with a mallet. Work the mallet around the edge, cross tapping to get it started and seated. The idea is to get the seal seated back in the case nice and square and flush so that it is running true to the crank. When I install them I put a very thin amount of motor oil on the seal face where it rides the crank only (not the o.d. where it seats in the case), just to help glide it in place a little. Make sure the new seal has the little spring running around the inside lip where it rides the crank, etc. They're actually pretty simple to get in, but if you screw it up you know how long it takes to get at it again...

I would recommend that you pick up "101 Projects for your Porsche 911" which is a book written by the owner of Pelican Parts and is available on this site. What you are asking about is covered in detail on page 33-34. It has tips that the Haynes manual and Bentley manual do not.

Make sure you observe the proper sequence and technique for tightening your flywheel bolts.

jcsjcs · jcsjcs's Garage

Cleaned up the area a bit and it looks good.

Tried to put the seal in a few times - but when I get one side in and tap the other, the in side pops out. A bit of a seesaw situation. Will try to work my way around.

I do have 101 projects - and reviewed Wayne's advice as well.

I think I need to be a more patient - so will do later on.

vulcan300 · 07-25-2010, 09:10 PM

Wayne's 101 project book shows the use of a ratchet extension to gently tap the seal in place. I most recently used a .5" x 1" x 6" piece of wood to the same effect. You can press the seal in a little with your hands making sure it is level on all sides and then small sharp taps on alternating sides until the seal is flush with the case. A little motor oil inside and outside the seal will help it slide into place. The three bolts in the center should be hand tight with a medium sized ratchet. If you want to torque them perhaps 15-18 NM? I'm not sure of the exact value as it wasn't in either the 101 projects book or the other reference I used. For an '84 torque on the Flywheel bolts is 90 NM and torque on the pressure plate bolts is 34 NM.

Good luck!

J

jcsjcs · jcsjcs's Garage

I was able to get the seal in after about 5 tries (it really likes to seesaw out if you don't get it just right.)

I used Wayne's method of the end of a socket - as it has a nice smooth end and does not mar the surface in anyway.

Very nice tight seal AND very satisfying when I finally got it.

It seems that I have found an interesting technique for these types of jobs:

1) Try over and over during the day and get really annoyed that you can't get it done!

2) Post a thread on Pelican board AND read a bunch of posts about the issue.

3) Do some other less "complicated" work.

4) Eat dinner, put the kids to bed, relax for a few hours.

5) Read all the posts that have accumulated during the day and get the necessary moral and technical support!

6) Go out to the garage at 9 pm with only the one job to do and get it done after a few tries.

This technique worked for RMS, replacing my shift coupler bushings, replacing a new fan belt that just seemed too tight, and so on.

E Sully · E Sully's Garage

The seal can be a bit stubborn. I did mine twice. The first time I set it too deep and it leaked a little. Second time I drove it in a little less and it seals great. There are also a few areas that Wayne shows in his book that you might want to use JB-weld on.