Cab leaking

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Andrew
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1987
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Ok folks, I have cleared debris from the wheel wells, sealed the ridiculous, two layer firewall and everything else I can think of and the cab still leaks into the driver and passenger side floors. I have brand new carpet and insulation and now I am back to square one. Do I just need to friggin duct tape a blue tarp all across the hood?
 

JamesSam

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This happens in my truck on the drivers side. It seems to land right under where the parking brake lever is. I believe it comes from the cowl. Notorious to happening to squares. Look there for another spot you can fill. I believe @AuroraGirl has put info up on here about this before.
 

dsteelejr

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My ‘80 K25 has the same problem, drips over the fuse block. One of the fuse block bolts has some surface rust from it. I was thinking of caulking it until the day I remove the cab for restoration bc I have a few holes in the floor in the usual places too.
 

Old Guy Bill

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In the bottom corner of the windshield channel on each side there is a small drain hole, it’s under the gasket. If this hole is blocked with debris or sealants the water will back up and get in between the two pieces of the windshield flange.
 

Radiohead

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Don't forget to look up. I was surprised/disappointed when I found this
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I'm sure I have cowl issues too, because I have the rusty fuse panel and rotted out parking brake cable & lever assembly too. All this to say its not always what you might expect. GL, but let us know what and how you fixed it. Pics are cool too.
 

gmbellew

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under the truck behind the fenders are the cowl drain exits. you may need to remove a plastic cover to see them. but you need to pull debris, flush from top, pull debris, and repeat until all the debris is removed. both sides.
 
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Ok folks, I have cleared debris from the wheel wells, sealed the ridiculous, two layer firewall and everything else I can think of and the cab still leaks into the driver and passenger side floors. I have brand new carpet and insulation and now I am back to square one. Do I just need to friggin duct tape a blue tarp all across the hood?
Update! I have decided for the time being to just JB Weld the screw holes for the kick plates over. It has been effective. They were seeping quite a bit. I also have a very slow drip by the heater box or whatever behind the glove compartment. Of course that one looks like it is beyond my time and capabilities. I also notice that the cowl drains really well but….on the passenger side, way up top, in that big well of space, there is a drip. It happens to drip right over the lip of that hole that the vent door sits in. I don’t know what to seal on the outside to stop this but from the inside will be impossible. I just want to seal that whole thing up. In the meantime it is easy to monitor with the kick plates off. If I can just stop the leak I will be happy and can find a different way to fasten the kick plates on, even if velcro.
 

gmbellew

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if water is sweeping in the kick plates, make sure you clean any debris from the cowl drain exit that is behind the front fender...when debris collects in that area, it builds up water faster than it can drain out and it will seep in the kick plate area.
 
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if water is sweeping in the kick plates, make sure you clean any debris from the cowl drain exit that is behind the front fender...when debris collects in that area, it builds up water faster than it can drain out and it will seep in the kick plate area.
Thanks! Yeah those are super clear. Flowing nicely. I also find a damn wasp’s nest up in there today too. The drip from above is going to be tough to locate/fix.
 

saltdog

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Pull the wipers and cowl and check the seam between firewall and dash - they will always leak there. Get it super clean and prime it, paint it, let dry, then seal it up. Flexseal worked great for me
 
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Hi Everyone!

So, I finally have an update on my leaky kick panels. Both panels have been off for sometime now. I JB welded every screw hole over and tested heavy water flow. Things looked ok.

In picture two, that is the drain hole many have mentioned on this forum. I ran a coat hanger all the way down and worked it in and out to ensure debris is gone.
The drain hole on the other side was interesting because it was covered by that rubber insulation you see also in picture 2. I mean totally covering the whole. I had to cut some of it out to uncover the hole. Also did the coat hanger in that one too. But I think this was probably affeecting my driver side.

In picture 3, you can see that I redrilled the two holes in the metal being the molding where you see the blue circles. My logic is that it's away from the flow of the water from the cowl and would be safe. I also used nylon tape around the screw threads and screwed it in slowly. I also filled the holes with 100% silicone before I installed the screws. I repeated this process for the two screws that hold the hood latch release. I didn't redrill any other holes. Instead, I used heavy duty velcro on the sheet metal and the corresponding area on the plastic trim to further fasten it. I feel a lot better having all of the holes toward the front of the truck welded over.

In picture 4, you can see the holes I chose not to redrill or screw. Velcro is also behind those spots. I figure it also makes it easier to get this piece off in the event of more leaks. I plan on grinding down some screws and just glueing the cap part in the holes to make it look more finished.

Picture 6 is your passenger side and it sucks. I ran water down the cowl and any hole you see circled in red seeps pretty badly. So far, I have JB welded the one at the bottom up again because it was the worst. I still have some decisions to make on how to finalize the passenger side. My AC seems to run better with that air flow door but I can't see how I can ensure it doesn't leak. I definitely need a new oval rubber seal on the back of what you see. But my concern is still those holes circles in red. I could use nylon thread tape on the screws there and 100% silicone also but I'm just not sure. In order to get that rubber seal to seat properly, I will need to have all screws firmly installed. I am not going to redrill any of the holes down by the floor and will repeat my velcro plan there.
 

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