Diagnoising Cab Leak

[erikhillard]

Trying to figure out where this water is coming from. New windshield and gasket fixed a lot of the water entering cab but there is still moisture on the passenger side which looks like its coming down behind the firewall material. Any ideas or suggestions of where to start?

I haven't glued down the new carpet I installed this summer because I was skeptical the windshield repairs were going to 100% seal the truck cab and I sure was correct.

Photo attached of damp area following a day of rain. Some silicone was added around the air vent body by my mechanic who did the windshield as a just in case but I'm not sure thats doing anything good or bad. He thought it might help but wasn't sure.

IMG_7839.jpg

[390FE1972]

It could be the wiper arm pivot gaskets need replaced? There is also some sealing that goes around the heater core inlet & outlet on the outside of the firewall & some foam / rubber square gaskets that go there (part 18596 in diagram). I also put some 3M fender sealant around the three bolts / nuts that hold the heater box to the firewall (part 33795-s in diagram). Here is a youtube from Autorestomod that shows them replacing the wiper arm pivot gaskets.

https://youtube.com/watch?v=YMgffFkvFpM
http://www.fordification.com/tech/image ... heater.jpg



Regards

[erikhillard]

Thanks for that video. Maybe I'll get lucky and its just the passenger side one thats leaking. That drivers side looks like a bear to do deal with.

[basketcase0302]

Permagum, (some folks call it "dum dum", (it's like a sticky play dough) is gonna be your friend here. Not sure if Lowe's would carry it in the weatherstripping department or not nut any HVAC supply store will have it on the shelf.

I
'd be money like mentioned above if it's not the wiper pivot gaskets. The hardest part of replacing those is getting up to them, (having to pull so much stuff out of the way under the dash).
But...I'd also bet on the heater cabinet mounting studs like mentioned above, (you can get a short term seal on these by using the permagum on the engine compartment side. And...also look real close at the holes where the heater hoses themselves penetrate the firewall which is another place the permagum will work.

Trick here is to stand on your head inside the cab floorboard with a flashlight once you at least pull the glove compartment out, while someone else goes to town with the water hose outside spraying all around.

[The Bandit]

To add to the possibility's of problems check the seam sealer on the other side of that area. If its raised up the pop it off and you will probably find a few extra holes through the firewall right there as mine was doing the same thing in the same spot.

[erikhillard]

Got the glove box one done but the drivers side is nuts. Any tips on getting that clip on and off so I can get the new gasket over the wiper post? The video mentioned a B Roll about it but I couldn't find it on their YouTube channel

[pcmdub]

Don't bother with the clip. Once you get that thing off, then you have to put it back on!!

Just turn the wiper on, then just turn the key off when it is out of the way.

[erikhillard]

Well, I went somewhat rouge. Ha. I have been installing double gaskets. The ones I got from LMC are paper so I made a second one out of thin rubber sheet from the hardware store. Installed rubber against the cab and then paper against the wiper.

Since I couldn't get the clip off for the drivers side, I made a slit in the gaskets at the top, opposite sides so the slits do not overlap. Put the gaskets on and hopefully since the slits are at the top and do not overlap, a good enough seal will keep the water out. Definitely 10,000x better than the original paper one that fell out in 6 different pieces when I pulled the 3 bolts.

Supposed to get an inch of rain tonight so we'll see tomorrow how it looks in the cab!

[basketcase0302]

Did not know anyone was making these using rubber or paper?
Mine from DC were cork.

Going into a pretty severe drought here with no rain for weeks and record temps.
Please send some of that rain our way!

[erikhillard]

I guess they could be cork but look more like thick pressed paper to me. The rubber ones I made myself by tracing and cutting out. In that video it looks like someone makes them in neoprene too.