Installing rear crank seal troubles.

[stubble88]

This is for an 83 911 using elring seal
Rear crank seal will not go on.
Am I supposed to use a little oil to get it on there?
Thought it was supposed to go on dry. But there is no way.

[yelcab1]

Confirm that you have the right seal.
Oil the inside lip of the seal to slide on the crank shaft.
Start the seal with your hand so it is seated into the hole, you may have it already as it shows in the picture.
Lightly tap with a hammer and a piece of 1x2 o 1x3 wood.
Once it gets started, firmly tap with the same piece of wood and hammer all around, in several places (opposite from each other) until the seal is flushed against the metal edge.

I just did this 2 days ago. No tools needed.

[stubble88]

The outside edge of motor is digging into the seal. It would go in backwards. So I’m guessing it’s the right size.

[stubble88]

I got it. Stuck it in the freezer for 10 minutes
Is it ok to use oil to slide on?

[356911930]

Stubble88,

Technically no oil on the OD of the seal, may cause a leak or allow the seal to "walkout". The ID should have a light coating of oil on the lip and on the crankshaft sealing surface.

Best of luck,

Rahl

[stubble88]

Originally Posted by 356911930

Stubble88,

Technically no oil on the OD of the seal, may cause a leak or allow the seal to "walkout". The ID should have a light coating of oil on the lip and on the crankshaft sealing surface.

Best of luck,

Rahl

Well I had a very thin application of oil in the OD but I wiped it off before going into the freezer. It’s in there so illl have to wait and see what happens.

Thanks

[john walker's workshop]

You also need to carefully work the lip over the crank flange bedore knocking it in place. I use a no bounce large plastic hammer and a plastic window tool on the lip. And dry on the OD.

[proporsche]

no need to put the seal in the freezer..it might be even worst idea since the seal will get brittle..Just start on one side -make sure the seal is over the crank with the lip..If you do not have a Porsche tool use flat head small hammer and bigger hammer tap on the small one..gently so..once you have it align you are done but show us the result before you bolt the flywheel...if you want to lube it prior installation use liquid soap - a little on the meeting edge....

Ivan

it is the correct seal one of the best in the market..

[Walt Fricke]

The reason you don't want to oil the OD is that it is friction which keeps the seal in place against the oil pressure, from a running engine, which is trying to spit the seal out. Liquid soap, though,is a sort of disappearing lubricant.

I'd be surprised if freezer temperatures would damage a rubber seal - freezers aren't any colder than engines in cars left out in Alaska or Finland overnight in winter. Not like liquid nitrogen.

[proporsche]

Walt... i agree with you about the freezing point,but for a novice trying to slide the seal over the crank .i would think it will create a trouble;-)


Ivan

[Walt Fricke]

The guy who taught me how to assemble a motor liked to leave the seal off until he was ready to put on the flywheel and after timing cams and so on. Thought it made the engine just that much easier to deal with. So I've done it that way when the case was apart, or when just replacing the seal. But it is something I always approach with more - what, trepidation? Worry about getting it right? - than other stuff like cam timing which is a piece of cake, even if it might take several tries, or getting the cylinders over the rings.

If freezing will let it just pop in, and all I have to be particularly careful about is the oiled sealing lip, then I might try it. Never thought of it, but the steel band part should contract some around the circumference under the rubber when cold. Shouldn't affect the ID part.

[proporsche]

i think people have trouble not with the outside of the seal but getting it over the crank...what i like to do sometimes ..i make the spring shorter by 3mm then i install the seal;-)

Ivan

[Walt Fricke]

I've tried the "shorten the garter spring" approach. It is easier to do than you might think.

A 911 mechanic once told me what he thought was the most important thing about the seal: if you don't get it entirely square to the crank snout, instead of contacting only a very narrow ring on the crank, you end up with the contact being a band. The band area can collect way more dust per revolution than a ring, and that dust can accelerate wear on the seal lip, so it will fail earlier than otherwise it might. Sounds like a good point.

Like many wear surfaces, if the crank shows signs of wear, you have a little leeway in where the seal lip sits, so it can be moved in a bit, or perhaps set out a bit. You don't want anything but the lip to touch the crank or flywheel.