Yummybud924

I think I screwed up and possibly made a huge sticky mess. I have a water leak under my dash and it's not the battery tray so I narrowed it down to the fan assembly (85.5 944 fan assembly).

anyways to reseal the fan assembly someone here told me to take it out and reseal it. Of course I wanted to try a shortcut and leave the fan assembly in. so I removed the top cover of the fan assmbly to be able to reach all round it where it seals.

I then bought a tub of rubberized ashpalt undercoating, thick goey black stuff. Say it dries and becomes permanently flexible.

anyways I took this crap and applied it all around the fan assemble where it meets teh metal and would leak water and applied a thick goe of this stuff all around it. Now that was 1.5 days ago and it is still gooey and sticky. It has become slightly more dry but is still very wet and gooey and can easily be formed.

Now tomorrow when I drive to school it will be raining and this crap is still goey and wet so when the rain gets on it will it make a huge mess of rubberized asphalt? and would the water prevent it from fully curing?

I expected this stuff to turn into a dry rubber coating like under my car. It says rubberized asphalt undercoating and is very thick tary stuff and it doesn't seem to be drying into a dry rubber at all.

hopefully it doesn't come off and keeps the water from leaking inside the car.

anyone use this stuff? will it eventually dry and in the mean time will water wreck it?

pjburges

Question - is this roofing tar you are using? I have used roofing tar to seal the fenderwells of my bodykit 944 with excellent results - HOWEVER - it does take forever to dry (heat helps) and is always somewhat spongy and sticky. I used the wet-dry version, which can be applied in the wet, and doesn wash off if it starts raining early.

V2Rocket

Is this the black gooey stuff that sticks to everything and comes in a red squeeze tube? I think its "3M Weatherstrip Adhesive"


That's the stuff I used on my taillights...never leaked since.

Yummybud924

no it came in a can and is rubberized ashpalt undercoating. Very thick black goey tar stuff. It's not roofing tar but might be the same, it's for automotive use, undercoating etc.

I'm worried as it doesn't seem like it is going to dry and looks like it will remain tary and goey.

Calmchaos

I used something similar in my battery tray. I applied it just thick enough to fill and cover the cracks.
It dried in about 4-5 hours.

Yummybud924

yeah that's why I'm worried, it's going to be 48 hours tomorrow and it has only formed a slightly dry skin but is still super wet and goo under the thin skin. I applied a pretty thick amount all around the fan assembly but still I would think it should dry by now.

even teh left over asphalt I got on a piece of paper is still wet and it's a thin layer.

xsboost90

undercoating???hhhahahahhaaahahaha--thats to spray on the bottom of your car to prevent knicks from road debris. Probl. wont seal much up very well. You shouldve used some tar rope seal or something.

MAGK944

Yummybud924, I gave you full instructions on how to do this. I did it on my car and it works great. The stuff you got was not meant as a sealant, it is used for preventing chipping of the paint and is used under the car etc where appearance is unimportant.

Only got one thing to say "DO IT ONCE AND DO IT RIGHT" HERE ARE THE INSTRUCTIONS AGAIN

1. Remove the thin plastic cover from between the windsheild and the bulkhead inside the engine bay.
2. Remove the six 10mm bolts and washers holding the fan assembly in place.
3. Disconnect the vacuum hose and electrical connections going to the fan assembly.
4. Remove the fan assembly by gently levering and rocking the whole assembly until the sealant breaks loose.
5. There is another vacuum hose to disconnect inside the fan assembly before you completely lift the thing out.
6.Remove as much of the old sealant as possible.
7. Replace with a bead of new sealant all around the lip of the fan assembly (no gaps).
8. Refit and bolt up. (Don't forget to fit the vacuum hose on the inside of the assembly beforehand).

This takes about two hours, but it is a PITA because the sealant does a good job of stopping you removing the assembly. You think is just isn't going to budge, then it does. You will be convinced that you missed a bolt somewhere. Better to have someone help you working either side of the engine bay. Also better with the hood removed, but can be done without.

Also, the thin plastic cover that you have to remove is very delicate, so take your time removing it. If I recall you will need to remove the winscreen wipers to remove it cleanly and gently pry it from where it is attached with double sided tape.

One final point to be careful of is the sensor on the RH fan assembly intake. It sticks out and can be broken easily, so take care.

You will probably find that most of the original sealant is still good, but in one or two places it will have hardened and there's your leak.

The sealant I used is a very good, non-hardening sealant. It is used for windshield replacement and is available at most auto stores. Product pictures below:

xsboost90

thats the stuff i was thinking of.

Yabo

Tifo must be ROFL.


FWIW, it should be dry by now. but if you put it too thick itll take a long time. Did you shake the can first?

pjburges

Yeah undercoat isnt the best sealer- wet/dry roofing tar will work much better because it's fibered- and has adhesives designed to seal [roofs] up. The wet/dry tar just takes a while to dry and will smell for a long time. It took my fenderwells about a month to really cure up and stop stinking.

The stuff everyone suggests you use is butyl rubber adhesive, which will work well for quite some time. Porsche used that on the windshield, as well as the cover for the gas and emissions lines in the back, and lots of other places as well. Thats definetly a solid way of fixing the problem.

There is a marine grade caulk adhesive that you can buy at west marine that is meant to be applied on boats below the waterline. It is incredible ****, you could substitute that for the butyl rubber.

Also, there is a outdoor window and door sealant caulk that you can buy at home depot. It comes in a black and orange canister, and the caulk itself is black. It is a derivative of butyl rubber, and works quite well, as you can press it into corners. Hopefully your undercoat will dry. lol

Yummybud924

lol yeah I didn't have time to remove the whole fan assembly so I applied undercoating in a tub all around the fan housing to help seal it.

I'm too busy with school and work don't have much time to work on the car but I will use that method later on to remove it and reseal it properly, thanks.

If I had spent an extra hour or two I could have done it properly. Now if I want to remove the fan assembly I'll have to remove a lot of tick tarry goop all around it.....

and now the undercating is still wet and I'm not sure if it is even sealing at all.

the back seat footwell aread on the driver side was damp again today but I'm not sure if it wetness leftover from last week. I'll have to wait and see if it floods again after sitting in the rain all day.

if it floods still I'll have to drill a few small holes in the floor pan to let it drain at least but that might cause rust problems later on.

Yabo

Please don't drill it,,, just fix the leak! work on it over the night or something.. think of the car!

Mighty Shilling

and a leak in the back seat footwell has NOTHING to do with the fan blower, and everything to do with sunroof drain tubes and seals, or the hatch separation/seal

xsboost90

well- could be the drain for the fan as well- sometimes they come undone- it can run down hill into the back seat but it would have to be some good amount of water.