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Posted by: 76-914 Feb 5 2023, 07:20 PM

Not sure which way this is supposed to be installed. The ones I removed are different so no help there. TIA, Kent
EDIT: I forgot to mention this is a 911 seal. Not 914.


Attached image(s)

Posted by: Superhawk996 Feb 5 2023, 11:05 PM

From photos I can’t tell - my sense of depth perception is whacked and I can’t tell which way the sea lip is oriented. I also can’t tell if I’m seeing a single lip seal or a double lip seal.

Sorry for crude drawing - failed art class. This is my best attempt finger painting on my phone.

Red is an example of a generic single lip seal profile - the lip should point inward toward the grease and where heat and air expansion will tend to apply pressure to the lip to help seal it

Yellow is exterior side - this is the environment side being kept out

Blue is the spindle it seals to.

Purple is what a generic double lip seal profile would add to a single lip seal



From what I think I see in top photo it’s a double lip seal and I believe the top photo is the correct orientation

Posted by: 76-914 Feb 6 2023, 10:18 AM

I'll take a better pic later today. I too looked at the seal thinking it would give me some clue as to its orientation. Both ends of the metal lip are equally radius'd (sp) so no help there. That indentation on the metal lip tells me there is a correct orientation. No worries and thx for that suggestion. I'm not going to be able to get back on it for another week or so anyway. Maybe the High Priest of Brakes & Bearings can shed some light on this @http://www.914world.com/bbs2/index.php?showuser=1110

Posted by: 76-914 Feb 6 2023, 11:03 AM

While I'm at it I might as well show you my CSOB inner bearing race install tool. I see HF has a set that are aluminum but the comments re: the handle coming loose so often I decided against that. Also, decent sets run ~$125. I didn't have an impact socket large enough to drive it in place so I came up with this. I took the 2 old races and spot welded the thinner edges together. Next I turned about .040" off one end of the races so it would not become engaged with the hub then drove it in with a hammer. I just realized I didn't show a pic of it after I turned it. I'll add that later this afternoon.





You can see the turned side as it doesn't have the discoloration from the welds.





And it does have 2 raised sealing rings. The beefier of the two is on top in this view.

Posted by: Superhawk996 Feb 6 2023, 08:07 PM

So it is a dual lip seal for sure.

As you have it in your hand, the side closest to your hand is the outside that faces the knuckle.

Posted by: 76-914 Feb 6 2023, 10:08 PM

Thx Super. I appreciate that info.

Posted by: malcolm2 Feb 6 2023, 10:19 PM

show some pix of it mounted that way. I would have bet that it mounted as your original picture.... But I have never driven a 911.

Posted by: Superhawk996 Feb 6 2023, 10:49 PM

The thicker portion of the dual lip seal has a garter spring behind it (circled in red) - the thicker lip that has the spring belongs on the inside toward the bearing.

Picture from 911 factory manual.


The smaller secondary seal, purple in my original “drawing” without the garter spring will always go to the outside. This secondary seal has little pressure on it. It’s main purpose is to simply keep debris away from the main seal so that it doesn’t become contaminated and wear prematurely.

Off topic seal trivia:
On seals used in very wet and very dirty environments they will sometimes have a third part of the seal called a flinger. Usually made of metal or rigid plastic. It’s purpose is to keep the super large debris / mud away from the rubber portions of the seal behind the flinger.

Posted by: 76-914 Feb 8 2023, 03:32 PM

Found this pic on the Pelican site.