Rear bumper to body seal question

[wjdunham]

I recently replace my rear bumper to body seal while I had the back end of the car taken apart for cleaning. I should have paid more attention when I took the old seal off, I wound up tearing it in a few places and threw it out before I started to put things back together. The new seal does not "stick out" as much as the old seal and leaves quite a bit more of the bumper exposed as can be seen in the attached photo, I used one of the less expensive OEM seals and though that may be the problem, but I just purchased a Porsche seal (at 2.5x the cost) and the profile does not seem appreciably different from the "OEM" seal. It is different, but not so much so that I think it is going to cover the now exposed areas. It is tucked in quite a bit farther under the signal light assembly than the old seal was. Any thoughts? It will be a real pain to take everything apart to get a new seal in there, want to make sure whatever I do is going to fix the problem.

I can't get the photo rotated properly, but the exposed bumper area can still be seen, it is the area that appears discolored due to the paint rubbing against the old seal (I think that's why it looks different anyway...).

Bill

[wjdunham]

Got the image rotated properly...

[juanbenae]

did you loosen the bumper mounts to set it where the old one sat? or did you just shove it in there?

[75 911s]

Yeah maybe the bumper is not all the way on. Did you put new rubber between the impact shocks and the bumper?

[pegasus9]

There is a ridge that the seal slides into. You can loosen the lens housing just a little bit to lift it and you will see where the groove is.

[wjdunham]

Originally Posted by 75 911s

Yeah maybe the bumper is not all the way on. Did you put new rubber between the impact shocks and the bumper?

I did put in new bumper shocks and all the associated rubber. I was careful to at least try and get it moved forward as far as it would go. I thought I had it in as far as it was when took it apart as the side bellows both went right on, the bolts right into their holes without having to tug on things. Also, doesn't fit properly under the signal lights and those are definitely in the right spot.

[wjdunham]

Originally Posted by aircooled pegasus

There is a ridge that the seal slides into. You can loosen the lens housing just a little bit to lift it and you will see where the groove is.

Not sure I understand? You mean the signal lens housing? Hard to describe how it is now, the rubber has a channel that I slid over the flat piece that the bottom of the signal light housing rests on. A photo of what you mean might help, I've tried googling for pics of how that seal is supposed to fit and not finding anything really helpful.

[75 911s]

Hear me out, and I apologize if this is way off. I've had my bumper on and off a dozen times. Looking at your picture, it looks like the wrong seal.

There are three pieces. One under each light housing (and the housing has a channel that the seal slides around and locks into.) and one reflector seal. The reflector seal has holes that the reflector mounts through. It cannot be removed without removing the reflector.

The seal you have there - is that perhaps the seal that goes between the valance and the bumper? Because it looks thin like the valance seal. The 3 seals above the bumper are thick and have an air channel as seen in one of my pics.

I don't mean to be offering up something that is way off base, but with the limited pictures I want to help you by ruling out a simple mistake.

Here's a few pics.

You can see the seal under the light housing here and the reflector seal. BTW these are on a 75. I'm not aware of this being changed later (i could be wrong!)







If the 3 seals are correct, there are slight adjustments in the bumper shocks (did you remove them at some point?) The brackets holding them down can be loosened, you can effectively point the impact shocks upward and then tighten the brackets down.

The bumper needs to be pushed up during assembly as well - so that these seals have no gap between the reflector and the bumper (so they get squished in a sense.) As the seal is squished it flattens out and thus gives you the original water mark line you have there on your bumper.

There is adjustment in the bumper bolts as well. Loosen the bolts, have a friend sit under the bumper and apply upward slight pressure then tighten the bolts down. The seal will squish out and the gap is reduced between the car and the bumper.

good luck!

[porschenut]

Originally Posted by wjdunham

It HAS to be the position of the rear bumper, and here's why.

Try to imagine where the seal would have to be to cover the now-exposed area on the top of the bumper. It would stick out WAY too far, right? The seal is exactly where it should be right now. And since the rear body of the car cannot have moved, the only other possibility is that the bumper position did.

You said you replaced the rear shocks and associated rubber. Well, that would certainly make a difference if the new shocks are not precisely the same length as the old ones. Plus, the old rubber had been compressed for 30 years or so, whereas the new rubber is fresh and uncompressed. That means the rubber mounting surface at the end of the shock is sticking out further than the old, compressed one did.

None of this should be a problem as long as you can clean and polish that area of the bumper that is now exposed. If that's just dirt or residue from the old seal, it should clean up very nicely and not be noticeable.

[wjdunham]

Thanks guys - as usual, the help here is always right on. I went out this morning and checked the bumper and it's definitely hanging too low, there is a small gap between the seal and the bumper. It didn't occur to me that the issue could be the height and not just the front/back alignment, and that the seal should get "squished" and thus will push out to the rear more (it's the only way it can go). Seems obvious now :-)

When I have some time I will loosen everything up and put some upward pressure on the bumper to get things lined up properly. I can also return the expensive Porsche seal and stick with the one that's on there now.

One additional note, it is the correct seal for the car, something must have changed over the years as my 1985 has a single seal that goes under both signal assemblies as well as under the rear reflector.

Thanks again!
Bill