flywheel main seal install

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boogie child
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flywheel main seal install

Post by boogie child » Mon May 01, 2017 9:58 pm

I am replacing my main seal and I remember seeing somewhere Colin saying he packed the spring area of the seal with grease. Wondering what kind. Or did I just make this up as I can't find the post? My understanding of the things to do: check and clean all mating surfaces, 45* cross hatch on flywheel mating surface, pack spring area with grease of some sort?, seal goes in dry no sealant?, oil or grease mating surfaces of the flywheel and the seal?
I have read a lot on this subject including how to check that the seal lip doesn't drop into a grove on the flywheel. My main questions are do I use grease in the seal if so what sort of grease, and which is best, grease or oil, on the seal and flywheel mating surfaces. there also seems to be dispute about using sealer to seat the seal or to seat it dry.
While I'm at it, grease, oil or sealant on the o-ring.
Oh and any other thoughts or wisdom on the general subject is always welcome.
Kent
82 air-cooled vanagon
82 2.0 air cooled the boogie bus

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Amskeptic
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Re: flywheel main seal install

Post by Amskeptic » Fri May 05, 2017 7:25 am

boogie child wrote:
Mon May 01, 2017 9:58 pm
I am replacing my main seal and I remember seeing somewhere Colin saying he packed the spring area of the seal with grease. Wondering what kind. Or did I just make this up as I can't find the post? My understanding of the things to do: check and clean all mating surfaces, 45* cross hatch on flywheel mating surface, pack spring area with grease of some sort?, seal goes in dry no sealant?, oil or grease mating surfaces of the flywheel and the seal?
I have read a lot on this subject including how to check that the seal lip doesn't drop into a grove on the flywheel. My main questions are do I use grease in the seal if so what sort of grease, and which is best, grease or oil, on the seal and flywheel mating surfaces. there also seems to be dispute about using sealer to seat the seal or to seat it dry.
While I'm at it, grease, oil or sealant on the o-ring.
Oh and any other thoughts or wisdom on the general subject is always welcome.
Kent
82 air-cooled vanagon


Yep, that was me. Grease in the inside channel of the seal acts as a "mastic" that pulls heat away from the lip. In an engine environment, the grease will quickly be rinsed away as the engine builds oil pressure, so pick a grease that is good for the engine, like moly.

I use Indian Head Shellac or Permatex Aviation 2h or whatever to glue the outer perimeter of the seal to the case for those hot hot hot moments where the case expands enough to allow the seal to loosen. I'm not sure that i have ever seen that occur, but that is my story.

IF your flywheel has a nasty seal lip groove, you need to make sure that you seat the new seal in a different spot by about 1/2 to a full mm. It can be done.
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

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boogie child
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Re: flywheel main seal install

Post by boogie child » Fri May 05, 2017 8:59 am

Thank you for the response that is what I was looking for.
Kent
82 2.0 air cooled the boogie bus

Keithinabus
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Re: flywheel main seal install

Post by Keithinabus » Mon Jul 03, 2017 5:20 pm

(I haven't figured out how to post a picture. Thought I did but said file too large)

From back of main seal to the outside of case, how deep should the seal be seated? Thanks, Keith

Read above 1mm. Is that right. I used the washer tool then the old seal and tapped the new seal in. I think I am seated deeper than 1mm.

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sgkent
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Re: flywheel main seal install

Post by sgkent » Tue Jul 04, 2017 2:59 pm

it depends on the seal type (part number) and the type of case as to what the factory wanted. Some seals protrude and some sit flush. That may sound like an evasive answer, it is not. You can spend 100 pages in a forum discussing VW flywheel seals. Generally if the old seal worked well for a long time try to match it in width and set it the same depth unless as Colin indicates, the surface area it contacts is damaged.
Thank You -

Merlin The Wrench

Machine Work/Shop Recommendations: http://kentcomputer.com/77VW/machinework.pdf

Pointers on rebuilding an engine: http://kentcomputer.com/77VW/rebuilding_a_vw_engine.pdf

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Re: flywheel main seal install

Post by Keithinabus » Tue Jul 04, 2017 3:11 pm

It's an upright as41 dual relief. Using elring orange seal. It is seated about 2mm deep. Not flush.

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Amskeptic
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Re: flywheel main seal install

Post by Amskeptic » Fri Jul 07, 2017 8:02 am

Keithinabus wrote:
Tue Jul 04, 2017 3:11 pm
It's an upright as41 dual relief. Using elring orange seal. It is seated about 2mm deep. Not flush.



Don't be concerned about insertion depth. The default would be to tap it in until it taps no further. When circumstances suggest a different depth, like avoiding a groove on the flywheel, then you can seat it a little less far with no ill effect.
Colin
BobD - 1978 Bus . . . . . . . . . . . 112,660 miles
Chloe - 1970 bus . . . . . . . . . . . 206,845 miles
Naranja - 1977 Westfalia . . . . . 112,885 miles
Pluck - 1973 Squareback . . . . . . 55,570 miles
Alexus - 1991 Lexus LS400 . . . 78,899 miles

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