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My 1965 Ford F-100 is leaking water somewhere up under the dasboard. When it rains, some water comes in and wets the padding on the front of the cab wall up behind the dash. When parked and it is raining, I can see a slow drip coming from up under the dash, location hard to determine. What is the most likely reason for a leak in this location? Windshield that isn't properly sealed? Hood vent? Other possibilities? Anyone had this problem that can help me narrow down my options for repair? BDMartin
I'll pick this one, "Windshield that isn't properly sealed?" since you stated "When it rains, some water comes in"
Without being able to see it to diagnose, it is hard to go further. Contact Dennis Carpenter for a replacement and have a local glass shop install it for you.
Run some water into the cowl, but keep it off the windshield, and watch under the dash. That way you may be able isolate between a windshield and the cowl.
Thanks GLRuff for the welcome and to the rest of you as well since good advice is about as welcoming as one could expect. Gee Wilikers Joe, Yyu're right, windshield isn't sealed. I know now because I followed the advice of Bertha66 (thanks) and ran water through the external vent only making sure none splashed up on the windshield. I think I ran a little too much water with too much force through the vent because some splashed out the side vents inside the cab but almost none dripped down from under the dash. There was one spot where a very small drip did come down from above, and after closer scrutiny up under the dash, I could see it seeping a tiny bit around the wiper blades. So I think gangstakr and garbz2 are also correct, bad seals/leathers around the wiper arms. Turns out everyone is right, bad windshield seal and also bad wiper blade seals. Thanks to all of you for your generous sharing of information. So I took Mr. Wilker's advice and ordered the correct windshield seal from Carpenter and spoke with Henderson Glass about resealing the windshield. But I have no idea where you go for something as obscure as wiper blade leathers or seals. Thanks everyone, it takes a village....BDMartin
Yup, did that, found the rusted floor pans first along both driver and passenger side. I have everything out of the cab except for the dash. I was about to weld in new floor pans but decided I should look into why the rust in the first place. Led me to the water leak, etc. I haven't had the truck very long, just getting started on the restore. So I'll first stop the leak by resealing the windshield, adding windshield wiper seals, and then I'll put in the new floor pans. I haven't installed these wiper seals before so I'm hoping it isn't too much of a challenge. Thanks for your help.
Welcome! looking forward to seeing some of your build once you get it going. My 66 had a leak just like that for a while and found it to be the windshield as well.
I'd lay odds Robert is right. If the window seal is leaking, it will leak up on top of the dash. If its leaking under the dash, the only place it could be coming from is from a wiper shaft hole. Bad gasket or NO gasket. I've see so many that didn't even have the gasket in place.
There is one other place frequently found on these trucks where the water comes in when moving, and you won't find it easily.
Where the "A" pillar joins the roof, the sealant was often insufficiently applied.
Look up under the gutter, where the upper windshield frame, "A" pillar and roof meet.
It left a hole where the rainwater would be pushed up against the windshield and up under the roof, where it would drip down on the inside.
This leak has caused quite a bit of rust up under the roof, down the "A" pillar, the firewall behind the padding and the cab floor and on almost every truk I have seen.
It is usually quite small, but big enough on some to slide a dime almost all the way in. It is usually bigger on the driver's side.