I have a 1986 F-250. Had it since new. When it was brand new I had the bottom of the truck undercoated. This year a leak has developed directly under the driver side floor. The carpet gets wet during rainy weather and takes a long time to dry out. I live in a rainy climate, so it's staying wet which is a no no. The wet spot is only on the flat well behind the pedals, but in front of the seat. it is not wet on the slope to the firewall. It is not wet next to the door either.

From underneath there appears to be no entry for the water, and there is no corresponding wet spot visible from below.

Anyone ever have this problem?

Thanks,
BigBlue2

 

yes i have this on out 84 f-250, on the drivers and passangers side the floor pans both rusted out b/c of the water leak

 

Were you able to tell where the water got in before the floor pans rusted out?

What I'm planning on doing now is to clean the bottom of the floor pan with soap and water, then using silicon, seal all the joints in the metal work, then spray the entire area with rubberized undercoat.

Anyone take exception to this idea?

BigBlue2

 

I have an 85 F-150 and when I lifted the carpet my whole drivers side underneath the pedels was rusted and pitted. I was suprised because I didn't have it in any mud holes or water for about 6 months. The carpet vinyl) was still wet also so I decided to do away with it. I removed the seat and the belts and started sanding. I primed the whole floor and then painted it over with two cans of Herculiner. Now all I do is hose it off when it gets muddy and I'm not worried about it being wet. I know, that doesn't solve the problem but I did find where it was leaking in from. Up underneath the dash way up on the firewall there was a plug where a clutch master cylinder could go and it was leaking into the cabin from there. But that's not all.. The water was first coming in from my dry-rotted, broken apart rubber seal that is supposed to prevent water from coming in where the hood line is. I would check all your rubber plugs on your firewall and doors for cracks or holes. It wouldn't be a bad idea to check the hood seal either. I hope you find the culprit, good luck..



-Ry

1985 F-150 302 4X4
Dana 44 TTB / 9 inch
4.56:1 Front/True-Trac
4.56:1 Rear/Detroit Locker
C-6 Tranny, NP208 Transfer
6 inch Skyjacker Class II lift
35 X 12.50 BFGoods AT's

 

my '82 leaks around the windshield somewhere and gets the floor wet.

 

Thanks for all the suggestions of where to look for leaks. Today I took off the kick panel and rolled up the carpet so i could inspect from above, and dry out the carpet. The top sie of the floor pan was perfect. No rust or holes, same as i saw on the bottom. But I did notice that the screws that hold down the kick plate go right through the floor pan. They're self tapping screws. Then I noticed that the pad under the carpet was soaked, even down by the door. The carper above was not wet. So here's what I think happened. Water entered throught the holes at the kick panel screws, wicked up the pad to the flat spot in the floor pan where water accumulated in several of the ribs in the floor pan that were stamped in for strength. Then when I got in the truck I would step on the carpet on the flat spot squeezing the water up through the carpet. That is why it appeared to be wet only on the flat!

Ok then, I'm drying out all the carpet. Then I'm going to silicon seal the screws for the kick plate as I insert them. then I'm going to hit each screw area with a couple shots of rubberized undercoat. I got some in a spray can. If this works I'll post the results here.

The kick plate was removed by a stereo installer on the drivers side only. That meant that the under coat and the seal at these screws was disturbed. The passenger side does not leak, and the screws on the kick have never been touched. To make sure I'll spray a bit more under coat on those screws too.

BigBlue2

 

Here's an update on my floor leaks. I sealed the holes for the screws on the kick plate with silicone. I had the carpet and pad lifted up to the tranny hump with a heater under there all night. That drove off the moisture in the carpet and pad. Today I took it for a test drive, Fortunately it's raining, and ran it all around town. Then I brought it back home and checked under the carpet for moisture and found little more than some minor condensation. I think the leak is in the kick panel screws.

Once in the garage, I decide to check the passenger side too. To my surprise the screws are loose the same as the driver's side. But there is no water in the carpet and pad on that side. I removed the screws and kick panel, and to my surprise there are little mini mole hills around each screw hole. Well this means that water and dirt are getting in the passenger side too. So why is it not wet like the driver's side? The answer is that the driver's side had no dirt build up around the screws. Only the passenger side had the dirt. The dirt was very fine and came in with water, but the dirt also acts as a self healing plug for the water. Makes sense, as the passenger side is always next to the shoulder, and that is the dirty side of the road. The driver's side is next to the crown, and that side is much cleaner. In fact when I siliconed the driver's side holes, only minor cleanup prep was needed. Not so on the passenger side.

I have a strong suspicion now that most wet floorboard problems start at the kick panel screws. These screws are steel and corroded quite a bit. I'm replacing them with stainless steel screws and then under coating the heck out of the general area.

I think this is going to solve my problem, I'll keep you posted on the progress.

BigBlue2

 

I'm happy to report that after a month of driving, and some of that in wet weather, that I now have no leaks and my carpet is dry. As it turns out the water was getting in through the self tapping screws in the kick plate under the door.

If you have wet floor boards on a 1986 Ford F-250, or a reasonable facimilie there of, you'd better check these screws. If they are loose or corroded at all replace them now with stainless steel screws. Seal the holes with silicon sealant as you screw in the replacements. Then as an added extra bonus I sprayed the area around the screws with a rubberized undercoating product. You can get this in a spray can at most auto supply stores.

I'd be willing to bet that these screws are the source of 99 percent of of the cases where the carpet is getting wet during rainy weather. When you think about it, it's pretty stupid to drill holes in the floor pan for the sole purpose of holding the carpet down. I would recommend that all you truckers check your screws today and make sure they are sealed. This applies especially to those of us that live in wet climates.



BigBlue2

 

my 86 F150 has a strange windshield leak. i have never experienced seeing water drip even during rain, but have noticed drips on the windshield seal on the driver's side after a rain.