Watertight 60-66 trucks

[66-PMD-GMC]

I noticed a lot of builders are using carpet in the trucks.
My question is, how is everyone keeping water out of their trucks and avoiding nasty moldy carpet??
Personally, I closed off every hole in my cab and I still get water in the cab.
I use the factory style rubber mat.

[jayoldschool]

Have you changed your windshield gasket?

[64fleetside]

My 64 pickup is the only vehicle I own that doesn't leak. I've replaced all the weatherstrip. I used Steele rubber on the W/S and vent windows.

My 96 GMC leaks like a sieve from somewhere, and it is the headliner apparently. I've had the third brakelight out, siliconed it back in and even resealed the roof seams, and it still leaks. The headliner gets wet.

[1963c-10]

I get a little blow by from my floor vents sometimes, but other than that i'm still leak free. Other than the window fuzzies & the rear window , all my seals are OEM that I know of.

[66-PMD-GMC]

My windshield does not leak.
Some of the grommets and plugs on the firewall leak and only when I am driving.
I have used a silicon non-hardening sealer on them and I am still getting a leak somewhere below the insulator pad and above the floor.
I have the truck completely apart now and when it goes back together this final time, I am seam sealing all seams and RTV will go on any and all grommets and/or plugs.
I have owned about a dozen of these trucks and every one had issues of water getting in some how or some way.
Since this is the last assembly of my 63, I want no (0) issues with water getting in if I drive it in the rain.

[64fleetside]

Seam seal the firewall/cowl seam, go nuts on it, inside and out. Wiper motor too.

[1963c-10]

x2 on the wiper motors. Was my nemesis on my original 63.

[Vernski]

Just keep it inside the shop and close the doors..Vernski

[Greg63]

Originally Posted by Vernski

Just keep it inside the shop and close the doors..Vernski

That's what works for me.
Greg.

[spacedebris]

The only leak that I ever had that I couldnt track down to an actual hole was water following wires in from the engine compartment. I had good seals everywhere and couldnt figure out where the 3 inches of water came from. Turns out water was following the wire through the grommet. So when you are done running all your wires, make double and triple sure that you use a good silicon to seal all through points on the firewall.

[66-PMD-GMC]

The one leak I found quickly when I had it together before was the grommet for the e-brake, that rectangular dude below the steering wheel.

As I said, I am looking for any possible leak locations that I haven't thought of before I button it up for the last time.
The vent doors that 1963c10 mentioned is one of those I hadn't thought of.
Thanks...

[kieth]

Man it never rains in Apache Junction any way........why worry ??????

I sealed my cab, added floor sound deadening then insulation, then installed a full firewall to back of cab rubber mat, then installed a stock rubber floor mat over that. No noise, no carpet to rot, no vacuuming, just sweep her out. Rubber floor mats are the only way to go.......cause its a truck.......ha ha Kieth

http://kieth.smugmug.com/Trucks/66-G...5345&k=QRXTmdg

[spacedebris]

Oh, thought of another. Now I dont know about the 60-66 models as I'm still building mine so I have no first hand experience with them, but on my s10, I had problems with the door drain holes getting plugged and water filling up the door cavity, and then entering the cab via the screw holes holding the door panel and speakers.

To fix that I made sure that I cleaned the drain holes good and keep them clean. Also I sprayed the bottom of my door with flex seal on everything other than the screws for the door panel (for obvious reasons) I just sealed them with plumbers tape.

[Hx16457]

Originally Posted by Vernski

Just keep it inside the shop and close the doors..Vernski

This is exactly what I am doing!!!! Plus I don't spray it with water to wash it. I use buckets and wash it inside the garage!

But, if you have a radio antenna, there is a hole under the dash (right side), and some times water can follow the antenna cable in to the cab, look there yet?

[66-PMD-GMC]

It rained most of the day yesterday so that is why I started thinking and then I ran across a few threads of guys installing carpet, (right Kieth?) so I made the post.

I'm not going to install carpet on my build but I did undercoat under the cab and also inside on the floor. I am running a stock style mat and nothing else.
I like to enjoy the metal growl of the motor.
I cut the antenna hole clean and installed a well sealed plug, in case I ever want to put a radio in her..
I am building a touring truck/pro-street and the original idea was to do this summers hot rod power tour, and as it goes, missed that one...
Shooting for the 2014 instead.
She isn't being built to hide in a garage...
I plan on putting half a million miles on her in 10 years..
I am sure I will encounter rain in my travels so that is why I am paying attention to every detail.

[BR3W CITY]

My truck has seen every kind of weather that isn't snow. Before the build started, it leaked from everywhere. Now, its pretty much always dry.

New winshield gasked made a HUGE difference. Triple check the a pillars and dash to cowl mounting area for damage, as a new gasket won't help if you have little dings on those areas....it will seep by. This was a big annoyance but is fixable.

Old firewall holes and grommets are always an issue. I use weatherstrip adhesive to hold plugs etc in place, and seam sealer on metal-to-metal overlaps.

Door seals being properly installed, and the doors being properly adjusted. You can smoke test a car for a couple $'s, and it'll tell you where its all coming from.

Heater core......if your getting wet, make sure its actually water.

Window channels and roof channel are another culprit. Mine have been removed and the roof seam filled with sealer. This stops the water from dripping to the rails and running slowly down the channel and into the fender/door/rocker seam...a prime place usually not fully coated or sealed on both sides, making it an easy place to seep water and rust.

Lastly, the actual floor. Pin holes in rusty floor seams, old seam sealer, rusted old repairs etc will all leech water. I replaced mine, then coated it with bedliner, and peel n stik on top of that.

When you park the truck, a small tupperware with some charcoal and a dryer sheet will help keep moisture out of your carpet, keep moisture off the inside of the winshield, and prevents any smell (and rodents don't like it either)

[66-PMD-GMC]

Thanks for the tips.
I have covered just about every one of those mentioned....
My cab is not rusted anywhere.. (Arizona)
I am trying to figure out how to build some kind of rotisserie for my cab..
I think it would make painting the cab 100% easier.....

[1963c-10]

Also check the drip rail to see what kind of condition the sealer is in or it can come down through the roof.

[kieth]

Hope you do not think I was being a smart ass" just kidding......Kieth

[66-PMD-GMC]

Originally Posted by 1963c-10

Also check the drip rail to see what kind of condition the sealer is in or it can come down through the roof.

Originally Posted by kieth

Hope you do not think I was being a smart ass" just kidding......Kieth

The roof skin was replaced and I seam sealed the living snot out of it.
I think the tunnel cover was leaking at the front of the cover...
I am getting lots of suggestions and appreciate it..
I hate getting something together just to find something is wrong requiring me to take it back apart again.
This will be the 4th time the truck has been assembled since getting it, narrowing the frame and then redoing the frame again.
Everything fits tight, straight, square and lines up perfect...
It will sit a little lower than I wanted to but all in all.. it looks good.
No Kieth, I didn't take your comment wrong. I don't think carpet looks right in these trucks at all.. never did..
But ya gotta respect whata guy does with his own truck... agree or not...

[MikeN]

If you've got a leak, water getting under that rubber mat is probably worse for your floorpan that water getting underneath carpet.

[66-PMD-GMC]

Originally Posted by MikeN

If you've got a leak, water getting under that rubber mat is probably worse for your floorpan that water getting underneath carpet.

YUP! You may be entirely correct and that is why I am exploring reasons and suspect locations for leaks.
However, carpet holds moisture in I would suspect... and grows mold..
That is one of the two main reasons I won't use carpet in my truck builds.
The second is that carpet just doesn't look period correct and holds dust and dirt, a big problem in dusty Arizona.
Looking at my bolt on transmission tunnel seal, I can tell that it never made contact or was ever sealing for about a 2 inch length in the front.
My frame is nearly done, need to finish up exhaust and other details that will be under the cab.
Once done, the cab goes on the chassis and real time leak detection will be happening on my cab, doors etc.. etc.. ...

[BigDan3131]

When I got my truck ir was rusted out and it only had rubber floor mats in it but then again it does rain here 9 months a year. Since its not a full resto that I'm doing to my truck I will shoot up as high as I can under the dash, the floor vents, the whole floor and the whole back wall with Rhino. I will texture from the seat mounts forward but that all.

Instead of using silicon to seal up everything try 3M Windshield Urethane once its setup it gets real firm almost hard unlike silicon and it can be painted over too. We use it to seal the seams on the roof's of trailers before I spray them with Rhino.

[TxRat]

every time it rained the floor on both sides of my truck floor would be wet. I found the where the kick panel and floor came together was rotted through and rain water would run down the cab drains from the grill in front of the windshield and wick into the cab. cut new panels in and no more wet carpet..

[66-PMD-GMC]

I water tested my cab today. Seam sealed, undercoated, sealed plugs and grommets.
Got a tiny bit of water through the main wiring that is next to the master cylinder, that was it.
The inside floor is undercoated too and the floor mat covers it all...
I used RTV on the harness, wrapped the cab up and will move on to finish everything on the chassis now, so when it is done, the cab can go on the completed rolling chassis including the drivetrain...
Thanks for all the tips..