MarkWiseman

I've been trying to stop the water leaks in my 1987 944 for a few months now, and after stripping the interior out I've got it down to 3 places.

LEAK 1 - Passenger (RHD) front footwell



The water slowly seeps through the gap in the kick panel and doesn't seem to come from anywhere else. To remedy this I intend to seal the gap on the inside of the car where the panels are spot welded together.

LEAK 2 - Sunroof inner seal onto back seats

This is a simple fix of replacing the inner seal (already replaced the outer one) and running a thin bead of sealer around the outer edge in the sunroof channel to stop it wicking. I will wait until I've put the headling back before I replace the seal which I have already bought.

LEAK 3 - Driver (RHD) under the front seat



This is the one I really need some help with. The leak is coming from the seat rail as indicated by the blue arrows. After removing the bungs in the chassis rail (or sill?) I can see that there is a small amount of water in there, I have no idea how it gets in, but it must leak through to a gap somewhere under the seat rail.

My question is how do I fix it?

Do you think it has blocked drains in the chassis rail box section? (maybe not as I don't suppose Porsche ever thought it would get water inside). There is virtually no rust inside, maybe I should just seal where the floorpan meets the seat rail to keep my interior dry, but then it could eventually rust out my floor pan...



What would the good menbers of this forum do to fix it?

Thanks,
Mark

rickb20

These are common problems. Most water leaks into 944's come thru the bottom of the battery tray, just above the footwell. Water entering there finds its way under the seat and into the rear footwell. If I were you, I would pull my battery and look both under the hood and under the dash panel for holes. If they aren't visible, have someone else mist the battery tray with water while you lay on the floorboard looking up.

If your sunroof is leaking it's usually not the fault of your seals, but most likely the drains that are plugged with trash. The tubing for the drains are made of brittle plastic and run through the C pillars. If they are not plugged they may instead be cracked, explaining some of the water in the rear footwells and under your seat. If they are plugged water will back up into the channels around the sunroof and then overflow into the car. It's tempting to push a wire into the drains but compressed air has less risk of puncturing the drain hoses. Replacing them is even better and you can use practically any type of hose as long as it's the same size. If I'm not mistaken, they run into the rear storage areas and drain under either side of the car. You should be able to see them from the underside of the car and can quickly determine whether they are plugged by watching there while someone else pours water in.

Edit --- I just noticed you have a right side driver, so maybe what I've said about the battery doesn't apply. Depends on where the battery is located on your model.

MarkWiseman

Hi Rickb20,

Thanks for the reply, but stripping out the interior was kind of a last resort for me after a few months of researching the common leaks on the forums and getting nowhere.

I had already checked for leaks around the front screen & rear hatch, I checked all 4 sunroof drains by placing a small funnel into each one in turn and emptying about a gallon of water down each one (to check for splits in the hoses too). I checked the Y piece that connects to the filler cap drain, and the hose as previously described too. The leak from the inner sunroof seal is pretty minor, just a few drips onto the back seat bases when it rains, as opposed to about a gallon in the rear footwell!

My battery is located in the rear, but I sprayed loads of water under the bonnet (engine cover) in the places either side where the battery would be fitted if mine was the earlier model. I can say for definate that my drains are clear and secure (the headlining is out and the trim pieces that fit to the windscreen pillars aswell).

The confusing part was that the rear footwell just seemed to fill up with water as if by magic, stripping the interior out was the only way I have been able to find it.

I don't know how the water is getting into the box section at the bottom of the door apperture, or if it would be safe to seal the floor.
If I did seal the floorpan would the hollow box section just fill up completely with rain water I wonder?!?

Thanks,
Mark.

River

had a friend with this issue too. especially in the back seats.

remember, we do have drains ALL over the dang car. Check the gas cap one. (it's not fun...it's not fun) lol!

MarkWiseman

I checked the Y piece that connects to the filler cap drain, and the hose as previously described too

I really think the water must be getting in at the front somewhere and finding it's way into that box section before leaking out through that seat mounting that's welded to the floorpan...
Water doesn't appear in the passenger compartment on that side anywhere, except from the seat mount.

MarkWiseman

Hi, I'm now thinking it would be better to cut a round hole, about 2 inches in diameter, into the top of the latitudinal box section that connects the inner sill to the seat mounting (bottom right of close-up floorpan photo) so that I can get inside it to either weld or seal it so that any water stays inside the sill.

That way if the sill doesn't have water drains then I can drill some, and it should keep the water from rusting the floorpan under the seat.

I can then waxoyl the floorpan inside the seat mounting through my new hole, and waxoyl the sill through the bung holes. This should hopefully slow down any corrosion inside the sill due to water and keep my carpets nice and dry.

If this sounds like a bad idea could someone shout asap before I get the grinder out!

EDIT:

By poking a piece of wire through the bung holes I can see that the box section leads into the sill like a T piece, so there is no point in drilling or cutting anything unless I intend to weld in a plate about 2" x 3" (which I do not). I put a hosepipe into the bung hole and pumped it full of water, there are loads of drains in the sill and they all work.

This seems a crazy design for a car maker, they know it will get water inside (or they wouldn't have put so many drains in it) so why port it inside the car so it leaks out and wets your carpets? I make these comments on the basis that my sills look totally original but if they are actually incorrectly fitted replacement then I appologise to Porsche in advance!

My final solution will have to be drilling a drain hole for the seat mount point cavity at the lowest point through the floorpan, seal up the whole of the seem between the seat mount point and the floorpan, then to spray waxoyl or an equivalent rustproofer into the sill & the seat mount point cavity and just hope for the best.

968 GUY

I mistakenly put a bolt that holds the seat rail down and poked a hole thru the floorboard. Sealed it up, and no leaks, but just luck that I noticed that.

968 GUY

Also, I may have missed this on one of your posts, but if you have AC, did you check that drain?

MarkWiseman

Thanks 968 GUY, I don't have AC on my car so that's one less thing to worry about!

I've drilled a drain hole in the floor and started sealing up the seat rail so there's no turning back now. I'm going to brush some brushable sealer over the top afterwards and then waxoyl everything in sight!