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Rear Main Seal Leaking After Replacement

Old 03-17-2017, 09:35 PM
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Guy
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Default Rear Main Seal Leaking After Replacement

Hello,

So after logging a few running hours on the "new" engine in my 79, I noticed the rear main seal is leaking pretty good. This doesn't surprise me......I installed in on the stand and forget to set it in flush (duh moment) It sits proud about 1/8 of an inch or so.

I am prepared for the inevitable.....pulling the clutch again BUT before I do, does anyone have any suggestions to set it in further with the clutch in place?

I know its a long shot, but I hate having to remove the clutch again, especially when it was working so well.......

Thanks
Old 03-17-2017, 09:49 PM
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GregBBRD
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Not possible.

Start the pulling.

BTW....I've been having terrible problems with rear main seals leaking....I had an engine which I tried 4 different seals in, before I got one to seal (switched brands.)

Irritating.
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Old 03-17-2017, 10:05 PM
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SeanR
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Originally Posted by GregBBRD
Not possible.

Start the pulling.

BTW....I've been having terrible problems with rear main seals leaking....I had an engine which I tried 4 different seals in, before I got one to seal (switched brands.)

Irritating.
You too?

The hell is going on? I thought it was just my dumbass having issues.
Old 03-17-2017, 10:11 PM
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Originally Posted by SeanR
You too?

The hell is going on? I thought it was just my dumbass having issues.
I did this job on the old engine as well without an issue. Used the pink colored seal. This one was black. Not sure I remember the brand.
Old 03-17-2017, 10:24 PM
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Originally Posted by GregBBRD
I had an engine which I tried 4 different seals in, before I got one to seal (switched brands.)
Originally Posted by SeanR
I thought it was just my dumbass having issues.
Awwrite: Give which brands are working and which aren't?

I'll be putting one in soon.
Old 03-18-2017, 12:30 AM
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Originally Posted by SeanR
You too?

The hell is going on? I thought it was just my dumbass having issues.
Fortunately, mine occurred on my test stand...pretty quick to change...but after 3 or 4, even that gets tedious. It's been so bad that I've been running engines on the test stand that I wouldn't normally run....I'd normally just toss them in. I had one engine I put so many seals in that I thought something had happened to my installation tool and I re-cut the different "steps" in my lathe.

I've fought this battle, before.....several times, in my life....with 911s.

I believe what happens is that a seal maker runs low and makes a new run of seals. Slightly different material or some other microscopic difference and the seal brand you've had work perfectly, for years, leaks like a fountain.

Soecifically, I've been having problems with the black seal with the metal "lead-in" lip....with "Porsche" molded into it. I'm sad to have this one leak, it is so much easier to install!

Because I've "played" this game before (911s use the same seal), I've got a main seal box with 6-7 different seal colors/styles....some might be 20 years old. White ones, red ones, black ones, black ones with red on the seal lip, etc.

I would have to check with Mary (she keeps track of stuff like this...so she knows what to order), but I believe I've been installing the more difficult to install (no metal leading in portion) black and red ones.
Old 03-18-2017, 01:20 AM
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Originally Posted by GregBBRD

I would have to check with Mary (she keeps track of stuff like this...so she knows what to order), but I believe I've been installing the more difficult to install (no metal leading in portion) black and red ones.
the Grey/black Porsche one installed on my fresh engine leaked as well. Greg got me a replacement "hard to install" Black/Orange one (dont know brand- no tapered lead in edge) and that did the trick. Tedious to install without the right "lubrication"...
Old 03-18-2017, 02:11 AM
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Originally Posted by granprixweiss928
the Grey/black Porsche one installed on my fresh engine leaked as well. Greg got me a replacement "hard to install" Black/Orange one (dont know brand- no tapered lead in edge) and that did the trick. Tedious to install without the right "lubrication"...
Yes, I've had 3 or 4 of those leak.

Sucks, as that was a great seal, before this.
Old 03-18-2017, 05:22 AM
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Have either of you used the metal installation tool #234 that you bolt onto the crank and wind down?

Seems like it would guide the seal into place pretty well or are you still using the old tool that you press onto?

As an auto owner I would like to know so that when I do it, I don't have to pull the engine or torque tube to do the job over.
Old 03-18-2017, 11:56 AM
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Hmmm... this might explain why my car seems to be leaking from the rear main seal after it was replaced as part of a torque tube rebuild.
Old 03-19-2017, 02:49 PM
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So I pulled the old seal today and I really do believe the seal was more the issue than the installation. Once the flywheel was out of the way, I found the seal to be flush and evenly installed. It was leaking from the removal cut out and from the crank to seal area. My old engine had a Beck Arnley seal and was dry as a bone after 1k miles. I am ordering another Beck seal to replace this failed seal.

The seal I removed was the one with the metal lip which made for easy installation but the lack of rubber ribbing I think may be an issue.
Old 03-19-2017, 03:01 PM
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Originally Posted by GregBBRD
I had an engine which I tried 4 different seals in, before I got one to seal (switched brands.)
Too bad our cars do not use VW part number: 716102 / 955 101 051 00

Same crank seal from the 1979 Rabbit which was also used in the Bugatti Veyron:

http://www.roadandtrack.com/car-cult...ugatti-veyron/
Old 03-19-2017, 03:14 PM
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Originally Posted by Hacker-Pschorr
Too bad our cars do not use VW part number: 716102 / 955 101 051 00

Same crank seal from the 1979 Rabbit which was also used in the Bugatti Veyron:

http://www.roadandtrack.com/car-cult...ugatti-veyron/
What is the size? It might be the same....

The 928 seal fits 911's, 944's, 968's.

The newer, modern design 911 seal fits....all Teflon, allow to sit for 24 hours before running, pray everything is perfect and it doesn't leak.
Old 03-19-2017, 03:23 PM
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So, Greg, are you recommending the new 911 seal, over the current black/red and black/grey seals, or just starting to try them out and not yet sure?
Old 03-19-2017, 03:31 PM
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Originally Posted by GregBBRD
What is the size? It might be the same....

The 928 seal fits 911's, 944's, 968's.

The newer, modern design 911 seal fits....all Teflon, allow to sit for 24 hours before running, pray everything is perfect and it doesn't leak.
The first place I looked it up, VW / Audi only list - I find a 997 101 212 01 part number in the mix. All the photos from 4-5 different manufactures all show a "traditional" looking seal. Searching the web for the 997 part number brings up this unit:

Amazon Amazon

or this one:
http://www.pelicanparts.com/More_Inf...101-212-01-M17


There's also a 955 part number which brings up this unit @ 85 X 105 X 11 mm:

http://www.pelicanparts.com/More_Inf...01-051-00-M104

Our crank seal -
Front: 60x85x10 mm
Rear: 90x110x12 mm

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