water leak both sides, firewall/cowl areas

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Swims350

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Ok guys I noticed my padding wet yesterday, removed it and the mat. So it's clean bare floors, well rusty ones LOL. Today and last night it rained, floors are wet, pass. side more so then anything. Truck has ac, no motor or trans in it, ac box intact from what I saw. The bottom of the inside heater box is wet, and it seems to be running down from one corner, dripping into the floor.

The driver's side seems to be droipping down from around the booster or steering column.

Is there anything under the outside cowl, I should look for? like a flap, vent or something besides the normal like rust holes?

I'm not sure if it's maybe the seal between the booster and firewall, or maybe between column bracket and firewall?

Same for ac box not sure if it's box getting full of water, or just seal between it and the firewall.

I can't put it in the garage to keep it dry right now, and I doubt I can take anything apart to fix it right now since the weather is getting bad. I may have to try taping some plastic to my front window and down to the hood to stop water getting in the cowl area.
 

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The times I've had leaks, it was from the windshield gasket. I know the sealer in the cowl area can dry out and crack, and if there's a buildup of debris in the cowl it can cause the seams to rust out.
 

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I've also had water come in from those areas through the seam in the bottom of the cowl. It leaks down between the metal layers and enters around various bolt holes - especially those for the brake booster/pedal assembly. That was a funky one to track down believe me.
 

Swims350

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I pulled the dash pad and checked all around the bottom of the windsheild gasket it was dry. My first thought was the glass seal of the door wing windows or glass, or even door seals and they don't shut all the way, need pins and bushings. Then I just felt around up under there and it was wet around the column and under the inside heater box.
 

1low4x4

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My white one does the same. I thought it was window gasket and may be. But I have rust near the firewall under the cowl. I may have to remove the cowl and address that. It leaks pretty good. On a hard rain it will fill up my weather tech floormats lol. And if water can get in so can noise and AC can get out
 

Swims350

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ac's going out anyways I have no need for it.
 

1low4x4

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crazy4offroad

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I used a liberal bead of silicone caulk inside my cowl, at the back where it meets the cab. I still say you're nuts for cutting the a/c out lol. I can't tell you how many times me and wife were on the pipeline or ridge running up the creek sweating to death on a 90 degree day with no a/c and 200+ degree engine in front of us and red-hot exhaust under our feet. If you can work around it I would leave it be.
 

crazy4offroad

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That's Probably got to do with living in West Virginia and not texas lol

The heat is probably worse here in WV compared to TX in the summer. 90 degrees with 90% humidity you feel like a steamed clam lol. Dry heat aint too bad, that's why over 100 don't seem bad to us hillbillies when we get in the desert lol.
 

Swims350

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That's Probably got to do with living in West Virginia and not texas lol


no wv sees triple digits with high humidty in the summer almost always and almost everyday. I just won't be driving it much to need it, alot cleaner looking without. I just roll windows down and open back glass. If we trail ride we'll be in the shade or get wet lol
 

Swims350

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there's only the box outside, the engine compressor and lines are gone and would all need replaced, and then charged and that's not cheap. The wife's van we need ac fixed for us in the summer
 

crazy4offroad

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Convert it to R-134a, you can buy that stuff at parts stores.
 

Swims350

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still the compressor aint cheap nor is the 134a to get enough of it to charge a full system and the gauges to do it right. I also have no condensor in front of the radiator.


I'll take it all out and let you have it. I want heat only stuff
 

Swims350

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if you got heat only I'll trade you, if not I'll have to find heat only stuff then remove. I was looking to get heat only inside firewall box, outside firewall box and blower, with the wiring and the controls with any cables that go to the box.
 

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