How do you replace the seal between the body and engine tin?

[frankc]

Originally Posted by Danish Dynamite

No, there was nothing cut off. It was the same all the way around. I bought mine at a Porsche dealer the other week.

Thanks. I was just getting ready to put my old seal back in, but the price of a new OEM seal is reasonable enough to justify replacement.

I should note that perhaps the material used on the replacement seal is improved over the original, because the rubber on the 20+ year old replacement - even over the muffler - still looks almost new and is very flexible.

[JJ 911SC]

Originally Posted by frankc

... Interestingly, the new replacement seal I purchased had the right half of the outer flap above the muffler (the section exposed to the heat) cut out (see photo). Perhaps this was causing an issue (burning rubber?) so they decided to simply remove that section, but it seems that of all places to seal, this is where you would want a good seal to avoid sucking in hot air to cool the engine.

Is your muffler on the right side?

For the 1974-89 models the is 2 version; NA and Turbo. Maybe one of them has a cutout?

[VFR750]

Just looked at my original seal, and that section is missing. This seems to be normal, from the factory.

I first thought it was damaged, but upon a closer examination, the cutout has nice square corners. This does not happen by chance. This was intentional.

Thanks for pointing this out. Saves other people from getting upset, when the new seal comes in, and has the cutout.

Not sure why it is there. Muffler is full length...

[PcarPhil]

My $0.02.

The seal below is a 930 seal. I believe the 911 seal does not have that cutout. There are different part numbers for 911 and 930 seals and I believe that cutout is the difference between the two seals.

The cutout goes above the turbo. I guess they did that to minimize melting the seal above the turbo.

Originally Posted by frankc

[frankc]

Originally Posted by Kaefer

The seal below is a 930 seal...The cutout goes above the turbo. I guess they did that to minimize melting the seal above the turbo.

Scott,
That would make perfect sense, however I just looked on PET and Pelican and see only one part number (911-504-111-02) listed for both 911s and 930s. Were these different at some point? Perhaps the two parts were superseded recently to a single part in an effort to reduce SKUs and inventory? And maybe what you get from the dealer is different from the OEM supplier?

Danish Dynamite said he obtained his from the dealer and it did not have the cutout. Hmmm, makes me wonder what I will receive if I order the OEM part.

VRF750,
From your signature it does not appear that your car is a 930, but you mentioned your old seal does have the cutout. Any chance the seal was already changed at some point in the past?

[frankc]

I take that back, the 930 number on Pelican is 930-504-170-01. Strange, on PET it shows the 911 part number.

[frankc]

Ok, I was looking at the 76-77 3.0L 930 PET catalog, which lists the 911-504-111-02 part. When I switch to any of the PET catalogs that include the 3.3L 930s, separate 911 and 930 part numbers are listed.

So it appears the 911 part number was used on the 3.0 liter 930s, but changed to the 930 part number (with the cutout) for the 3.3 liter cars. Is the turbo in a different location on the 3.3L cars?

[Ronnie's.930]

The turbo is in the same location for the 3.0s and 3.3s, but the reason for the cutout on the 3.3, 930 rubber seal is that the catalytic converter, which was installed at some point on the 3.3s, is on the right side, above the muffler, and almost touches the bottom side of the engine tin (it runs left to right - parallel to the muffler). The cutout section is not above the turbo as the turbo is on the left and the cutout is on the right.

One other bit of possibly interesting info is, that it is good to use the cutout version on a 930, even with the cat removed (like mine is) because most aftermarket mufflers then go in the space that the cat occupied and are very close to the engine tin.

[VFR750]

frankc,

The seal may have been replaced before. Hard to tell. Yes my car is a SC, so I do not have that issue of the CAT being right there.

But oddly, I have a hard wear spot on the tin, that goes all the way through the tin, on the RHS. It is not rust. There is a taper to the edge of the hole. Any chance the large SC muffler contacted this location?

Theory: since the muffler is a 1 in 1 out, and hard mounted on the left to the CAT, maybe the RHS of the muffler gets tipped upwards during operation, and gets very close to the rubber.

Maybe that is why Porsche went to the cutout, to get clearance to the tilting muffler.

[VFR750]

Originally Posted by VFR750

Theory: since the muffler is a 1 in 1 out, and hard mounted on the left to the CAT, maybe the RHS of the muffler gets tipped upwards during operation, and gets very close to the rubber.

Maybe that is why Porsche went to the cutout, to get clearance to the tilting muffler.

Theory CONFIRMED

The SC has the cutout, because the muffler would be too close to the seal and potentially burn it.

Here is the wear on the muffler and tin, that confirms the close proximity of the muffler.

The cutout makes sense for the 1975 and on cars, because they had the 1-in style muffler. With SSI and a 2-in muffler, I could go to the full seal.

[VFR750]

This might also explain why the rear tin is only rusty on this side. The heat from the muffler probably burned off the paint, rust happens....

[JJ 911SC]

Originally Posted by VFR750

... The SC has the cutout, because the muffler would be too close to the seal and potentially burn it...

While the 3.2 does not come close enough, my SC body has the one with the cutout.

[frankc]

Sorry to bring this topic back, but I ordered a new seal 911.504.111.02 from our host because I wanted one without the cut-out section. It arrived today and it has the cut-out! I guess I will be returning it, but what do I order instead?

Has anyone ordered one of these recently and it not have the cut-out? I am wondering if it has to do with the "OEM' vs. genuine Porsche part (I ordered the "OEM").

[ROW911SC]

Can both seals be replaced without dropping the engine?

[lespaul]

While on the topic of seals, how have you dealt with the pieces of tar impregnated foam that are stuffed between the back (towards the front of the car) wall of the engine bay and the support for the rear shocks? Mine were very nasty. Does anyone offer replacements? I would think that a better (cleaner) solution might be to glue something like the rubber seal that is the subject of this thread into the gap. Or -- a strip of garage door bottom sealer rubber.

[JJ 911SC]

Bought 2, never used them... Pelican Parts - European Automotive Parts and Accessories - Porsche • BMW • Mercedes • Volkswagen • Audi • Saab • Volvo • MINI

He is a thread about peplacement: Engine Bay Foam inserts?

[ROW911SC]

I assume that these seals cannot be replaced without dropping the engine?

Thanks.

[lespaul]

Thanks JJ.

Brad

[ROW911SC]

Originally Posted by LenS

I assume that these seals cannot be replaced without dropping the engine?

Thanks.

Anyone?

[Robey5]

LenS:

The seal that is being referred to is one which seals the engine tin to the body. Can it be replaced without a full drop?

Maybe. However, I can say that you would have to be a contortionist with very flexible hands and a creative approach to pull this off, because getting the new "U" shaped seal will be in a very tight area where you will come in contact with the rear engine bar, the blower motor for the heat (if your car is equipped) and the exhaust ... and that is on the left side only! On the right side, you're going to have a little more room - if you have a CIS engine...but this job will be very tough if you do not have the engine out of the car.

Now, speaking in terms of a better approach? A partial drop MAY be a possibility. There again, your hands are going to have to be rather flexible to get the one near the fire wall installed.

This is a job that is best done when your engine is out; and I had to replace a chunk of the rail that holds the seal in. Good luck!