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Rear main seal

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Sometimeman Casual Dubber

24 posts · joined Feb 2009 ·

#708671
Ah, There is no rest. Put motor back together, very carefully. Went for drive of about 150 K's and it ran pretty well I thought, However after it sat sat for a while ie over lunch it started to bleed... Have not tried it again yet. I am sure it is engine oil, coming from the connection to the gearbox. We used a seal from Vintage, the old one was buckled. I think we put the seal in correctly but have since heard that it should be recessed about 3mm, Now I can't recall if we did that, perhaps just flush with the casing. Is it possible the leak is just excess from the installation that warmed up then found its way out....Or am I being really wildly optimistic?

1500S Custom Title Time!

1,418 posts · joined Mar 2005 ·

#708688
Optimistic!!! Volkswagen designed it to be flush with the case end. If that's how you have it then it's right. The VW oil seal installation tool ensures that the seal is pushed flush. If it's in 3mm then it's assembled wrong.. What is the condition of the seal surface on the flywheel?

DH

silver Dangerous when poked

2,169 posts · joined Dec 2002 ·

#708690
What model is it?? did you put the O'ring in the fly wheel??
Keeping it real !

vw54 Administrator Always Waiting 4 Friday

16,723 posts · joined Aug 2002 ·

#708748
did you polish the seal lip area on the flywheel if its grooved it will leak

and did you fit the oring as well
I read it on FACEBOOK so it must be true


http://forums.aussieveedubbers.com/viewtopic.php?tid=91278&page=1#pid848630


http://forums.aussieveedubbers.com/viewtopic.php?tid=63561&page=1#pid624099


http://forums.aussieveedubbers.com/viewtopic.php?tid=4832&page=1#pid452603


http://forums.aussieveedubbers.com/viewtopic.php?tid=60650&page=1#pid574409

Sometimeman Casual Dubber

24 posts · joined Feb 2009 ·

#708776
Hi, It is a 65 I believe. There was no O ring. The information re the 3mm came from Korrine at vintage, I rang re some more parts and she asked the 'guys out the back' They also said some early flywheels did not have the O ring....Will one fit mine and if so what size and where does it go? The flywheel was given a smmothing to make sure there were no grooves, though it was very good as it was. None of the books I have mention an O ring...I have Henry Elfrink, Autobooks by ken Hall, Gregorys and Scientific Publications....How come They don't mention the ring? Thanks Guys

Sometimeman Casual Dubber

24 posts · joined Feb 2009 ·

#708778
This guy is a dill... I SHOULD have looked closer...Now I see It.... Duh

grumble Son of Jim - Creator of Good

2,672 posts · joined Jun 2008 ·

#708827
The other possibility is that the No 1 main bearing is floating in the crankcase,this is a major source of oil leaks.

Menangler Custom Title Time!

1,991 posts · joined Aug 2002 ·

#708850
Flywheel oil seal flush with the case??? that is not right.

It needs to be pushed in as far as it will go, until the seal bottoms out in the case and the factory tool will do that, the outside of the seal will end up being about 3mm further into the case not flush.
FAHRVERGNUGEN;
Description of a pleasurable sensation,
Experienced when a car and it's driver are in mutual harmony, A unique driving experience, Pleasure, Satisfaction,
A feeling experienced by Volkswagen Drivers.

1500S Custom Title Time!

1,418 posts · joined Mar 2005 ·

#708872
Menangler wrote:Flywheel oil seal flush with the case??? that is not right.

It needs to be pushed in as far as it will go, until the seal bottoms out in the case and the factory tool will do that, the outside of the seal will end up being about 3mm further into the case not flush.
Install tools vary from flush to 1.5mm max below face. With the seal flush there is still clearance on the radius of the flywheel and the seal. Many of the VW trained mechanics of the 60s used a piece of smooth timber for their "home installer" to drive the seal flush with the case.
Their engines didn't leak oil back then.

The main cause of leaks here are:

1. The seal damaged due to poor installation by using a hammer

2. The flywheel has a groove worn into it.

3. Too much end float or loose No. 1 bearing in case.

4. Blocked drain hole from front cavity to sump due to use of sealant. Is this hole clear? If not the pressure will build up and oil will bypass the seal.

There is no need to use any sealant on the seal/case bore. Also, the reason many push the seal into the bore further (3mm) if it will go that far is to get the lip onto a clean surface of the flywheel to provide a seal. Better to have the surface machined if the groove has just started. The energised type of seal we use will seal still if the diameter is a few thou undersize.

DH

dangerous 23 Windows of Awesome

5,901 posts · joined Jan 2005 ·

#708905
Just for reference I always install mine flush.
Sometimes if they are set in too far,
the cavity that remains is too small
and the oil can build up insude that cavity very fast at high rpm....even if the drain back hole is clear.

The problem can be agrivated with excessive oil clearance in the rear journal (did you check oil clearances?).

This is true for boat anchors that have a pulley seal too, (justkidding).

If the FW and crank is an early one without the O-ring it must use a paper gasket.
Although I am sure modern technolog has produced a sealant that will do the same job, better.

Naturally end float should be checked and set when ever you have the engine apart.
westi wrote:That's mad Alan.

1500S Custom Title Time!

1,418 posts · joined Mar 2005 ·

#708955
Good info in that post Joel.

DH

bigrudi Wolfsburg Wizard

401 posts · joined Apr 2005 ·

#708990
also check where the seal sits in the case someone may have damaged this area when removing the old seal Rudi

dangerous 23 Windows of Awesome

5,901 posts · joined Jan 2005 ·

#709048
Joel wrote:well everyone knows i tap mine in just flush........

http://forums.aussieveedubbers.com/viewtopic.php?tid=58377#pid553860

and none of them are leaking yet
Good stuff Joel.
Just another personal preference thng....,
I like to do the end float before I fit the seal.
This has a few benefits,
one of which avoids the seal being damaged
trying to get the shims past the lip.
westi wrote:That's mad Alan.

Menangler Custom Title Time!

1,991 posts · joined Aug 2002 ·

#710273
The following is word for word from the factory service manual;

Install new oil seal, using Tool VW 204. screw the tool into crankshaft and insert oil seal by tightening the guide piece, The oil seal must bed squarely on the bottom of its resess.

This leaves the oil seal sitting about 2mm inside the case and the inside sealing lip of the seal on the correct part of the flywheel, if everything is in good condition it won't leak.

Also VW did a dealer rework sometime in the '70s and enlarged the oil return hole in the case behind the oil seal as there was problems with oil not returning to the sump fast enough and building up behind the seal and leaking, this was done by removing the engine, flywheel, oil seal, using a drill to enlarge the hole, cleaning up the mess!! fitting a new oil seal then putting everything back together and leaky rear main oil seal problem fixed. One of out old local Mechanics worked for Pound Motors in Melbourne in the 70's and did 100's of them as an apprentice.
FAHRVERGNUGEN;
Description of a pleasurable sensation,
Experienced when a car and it's driver are in mutual harmony, A unique driving experience, Pleasure, Satisfaction,
A feeling experienced by Volkswagen Drivers.

Sometimeman Casual Dubber

24 posts · joined Feb 2009 ·

#711026
Thanks for all the good advice everyone. The final ???? solution seems to have been to put a Speedy Sleeve on the flywheel as it was felt that there was not enough pressure on the seal.. Went for a 100 mile drive and all seems well so far....................................However when I got home and left the car overnight I was greeted with 2 oil leaks and they are from the gearbox...........I think I now need a new thread, so ever onward.

Cheers Ian