Getting water in the cab somehow

[OldRedFord]

I need to replace the drivers side floor pan, and figure out where the water is getting in from. The water does not seem to be coming in from the windshield or the cowl. I pulled the instrument cluster and looked behind it and there is no staining on the firewall. Maybe the lower seam on the firewall, between the floor pan and the wall?

[fordman]

the windshield wiper rotor gaskets maybe. if they arent leakign that could just be water from wet feet over the years.

[rlgrantjr]

When I got my truck earlier this year every firewall penetration leaked, but the worst offenders were the windshield wiper pivots. I've got them all fixed but the drivers side pivot and it leaks a lot. My floors were really bad but I've patched em up and painted them with rust inhibiting paint. Once I fix the last leak the floor will get roll on bedliner applied.

[Banjo]

I was so mad at mine, I took everything out of the dash and rebuilt the heater box while it was out. Instead of using gaskets for the windshield wiper transmissions, I used black rubber cement kind of stuff they make in a caulk tube for chimney flashing (about $5 per tube I guess). I used the same stuff anywhere else I thought and mine is staying dry. Those wiper transmissions are HARD to get to and fix, you about have to have everything out of the way to work.

[Joshpow]

The wiper pivots, windshield, and firewall seam are the only three things coming to mind. If the latter aren't leaking, I'd check the pivots.

[JMcTurnan]

Wiper gaskets, the wiring harness where it goes into firewall may not have the grommet on it, nore the antenna grommet.

[1971ford]

Is there actually water there or are you figuring that there must be a leak since the floor is rusted? If is probably from front tire salt/water spray and wet feet unless you know there definitely is a leak that could of caused all the rust.

[cdeal28078]

I know the cowl on my 71 leaks. I try to keep her out of the rain these days. I am going to hit up the magnetic sign guy this week and get a blank sheet of the stuff as close to the color of my truck so when I DO have to get her wet I can keep most of the water out of the cowls. I sealed up everything I could when I painted my truck about 9 years ago including replacing the wiper pivot points.
clint

[Joshpow]

The magnet sheet is a great thing. You can also use it to keep trash out of the cowl area while parked. I plan to get some for the ol 72 sometime.

[FoMoCo]

I replaced the wiper gaskets with butyle tape. Kinda like dumb-dumb made for installing windsheilds. I know they,re not leaking. While driving in the rain I can almost watch the water coming in from between the windsheild and windsheild post. I've been chasing it with clear RTV sealer with little results. Looks like a new gasket in store for the winter. Cowl and drains are super clean. All inside cowl seams were sealed with seam sealer and painted.

Nick

[fordman]

the windshield will leak at the roof and pillar seam on top of the windshield on these trucks that is where you use your flowable silicone at. it worked on my 93 and my 94 too.

[fireguywtc]

I was thinking today, perhaps that seal where the steering wheel column goes through the firewall might be a culprit. Perhaps some spray or run off is getting into that.

[FORDification]

You just need to get up under the dash with a flashlight while a buddy sprays the firewall down with a high-pressure hose, so you can see where the water comes in.

[OldRedFord]

Today after it rained all last night (Tuesday night into Wednesday) I went out and looked and noticed some water on top of the transmission hump. Also there is a bit of staining around one of the windshield wiper grommits. (The one that is behind the radio hole)

The water on the transmission hump is coming from the middle of the top of the windshield. There is also a gaping hole where the rod for the gas pedal passes through the firewall. Why I didn't see that before I don't know. The grommet for the brake looks good.

[fordman]

the gas pedal originally had a putty tape stuff around it when installed. the wiper pivots used a cork gasket to seal up.