Help on #8 bearing Seal Again

[sayah]

This will be my 3rd attempt to stop an enoying leak from this area and have noticed that in my previous attempts that the snug fit of the seal tends to tear the rubber on the top near the bearing where it is notched. (The notch is there to facilitate removal, I assume. Ironic isn't it.)

I purchased the seal (50x30x10) from our host. The seal itself looks different in construction from the one in the Haynes manuel. Not inferior, just different.

My questions are:

Is this seal slightly too large? When I go to install it, it is a real struggle. Would it not be better to dress outer edge with the blue stuff of a slightly smaller seal, say 48x30x10, for example and have a snug fit rather than this super tight fit? I know why its snug, but it shouldn't destroy itself during instalation. How does everyone who does their own work install this seal without tearing the outside rubber coating on the notch at the top of the bearing?

Thanks
Sayah

[Zendalar]

if u mean the rubber/silicone seal behind the flywheel, I simply used big plastic tube, put it on the rubber, and gave it some rubber hammer. It tore a bit, but does not leak + i gave it some silicone on the outer edges.

[Tim L]

If your talking about the pulley side. I use a feeler gage to cover the notch so it doesn't rip the rubber.

Tim

[sayah]

No, this is on the opposite end, under the crank pully. I know this area probabily fills with oil since it looks like pressure builds behind the seal. If any flaws are apparent it needs to keep low pressure oil from leaking out and probabily needs to be perfect.

[john walker's workshop]

use the red/black seal. they're tougher than the white ones.

[GB83SC]

OK I am confused!
I just changed out my intermeadiate shaft cover oil ring to stop a little drip and it is bone dry now.
Where is this #8 bearing seal at?
Any pictures?
Thanks.

[john70t]

I don't know if this will apply in your case, but on trailers hubs filled with oil I've used "copper-coat" sealant on the outside ring and a good smear of white lithium grease to retain the spring and lube the seal on install. Also, repositioning the new seal to sit furthur out/in on the shaft helps if there has been a groove worn into it.

[sayah]

GB83SC, the seal is just above the intermediate shaft cover, directly behind the lower fan pully.

I have ordered another oil seal from our host since everyone who responded so far has not mentioned a misfit of the seal itself, rather emphasised the correct instalation to get keep things dry.

[Roland Kunz]

Hello

AFIR is 50 x 30 x 10 the correct size but since the 996 uses the 50 x 30 x 10 Porsche replaced the old stocks with the new ones.

Grüsse

[Wayne 962]

Hmm, seems to be a LOT of confusion on this. Let me go to my "Engine Rebuild Book" picture library...

Install the seal flat into the bearing (you should remove the muffler, sheet metal, and mount to get at it properly). It should go in without much effort. Use a bit of Curil-T on the outside of the seal to guard against leaks...

-Wayne

[sayah]

Thanks Wayne, the pictures of the seal and bearing are great. The problem appears to come because any damage to the seal or wear on the seal over the crankshaft will cause a leak since the oil pressure in this area is high.

[jabb]

I had the same problem tore 3 seals on that notch.
I greased the outside of the seal with some clear silicone grease.

Then insert the seal on an angle with the top angled in toward the notch and work around slowly with your thumb gradually pushing it into place. I found the seal at a local Autoparts store
so did not have to wait for Left Coast delievery.... Just take your time and grease up the outer part of the seal and work in slowly

[Roland Kunz]

Hello

Type error:

The old seals had 8 mm and you could shop 9, 10 to run the lip on a ungroved surface.

Grüsse

[Wayne 962]

Perhaps there's a burr (Raymond) or something on your notch. I've never seen my rip...

-Wayne

[Tim L]

Mine ripped on the notch also. I used a thin feeler gage to cover the notch so it doesn't rip the rubber then pull the gage after the rubber starts past the notch. I didn't want to ripe another one. I also used a little lube.

Tim

[sayah]

Thanks Tim, I orderd a new seal from our host, so I will attempt to install this again. Looks like no one thinks the seal is too big or incorrectly sized. Funny some thing it is just a snug fit while most need to resort to extremes, like this feeler guage trick, to get the dam thing in without ruining it. Wonder how many install it incorrectly, not knowing the damage was done, then blame this on the #8 o-ring.

[Jim Sims]

If my notch was tearing seals I'd break the inside sharp edges and ensure there wasn't any burrs. Jim

[TimT]

yes its a good idea to relieve all the sharp edges on the bearing before you install the seal. the use some sealant (lube) when you install the seal. Also when you install the bearing in the case smear a little sealant around the o-ring on the bearing before you tighten the case halves. I like to use the dow white sealant, but its $70 a tube...... like with most things..... you get what you pay for

[Tinker]

Are you sure it is the seal that is leaking and not the O ring? That area is notorious for leaking from the O ring around the #8 bearing on motors with high mileage, especially if it was not assembled with the latest style green O ring.

Tinker

[sayah]

Tinker, the mechanical guru at Sportique Porsche looked at me like I was about to be executed when I mentioned to him the possibility of leakage from the "o" ring. He didn't go into detail but the seal not the "o" ring is where the problem lies. This makes sense when you consider the oil galley supplies oil pressure directly behind the seal. The cavity behind the seal fills with oil and this oil is under direct pressure from the pump.