Floor covering and sound deadening in wet climates

[67sport]

Just Friday night thinking...

Have any of you got a solution to adding sound deadening and/or floor covering that is somewhat resistant to standing water? I wouldn't want bedliner or spray anything, but I would like some deadening.

My 'nice' Bronco is a mostly stock 74 with the original rubber mat in the front. It's insured for about 9 months of the year, and where I am it rains frequently for 5 of those. It has a decent canopy and newish seals everywhere, but it leaks and I see no practical way for that to change. I've owned Broncos for 25 years. They leak.

I'm thinking that adding some dynomat or even hot water tank wrap under the rubber mat/firewall/canopy would help. I have covered storage so if I did it right I could lift the floor covering to let it dry out from time to time.

Any experience with how much it helps or techniques that have worked?

thanks.

 

[Wild horse 75]

Dynamat won’t hold water. I would steer clear of anything with a foam pad or jute. The dynamic can go right under your rubber mat and be fine.

 

[67sport]

Couple more questions.
What thickness works well and still allows the factory mat to fit right?
Are the pre-cut squares or rolls easier to work with?
Both dynamat and the knock-offs look like they are self adhesive. If the product doesn't hold water, how does any trapped water get dealt with? I guess you can't lift it off the floor to let air circulate?
Edit - I see there are non-adhesive versions too.

 

[Yeller]

The dynomat foil covered butyl products do a good job of protecting from water intrusion reaching the metal, any standing water just sits on top of it. It is a pain to remove but works well.

 

[Wild horse 75]

Just make sure your surface is cleaned really well before application. Any surface rust should be wire brushed off then coated with primer and paint. Then when you stick it down just make sure you work it into every contour of the floor. As long as there aren’t any gaps water shouldn’t get under it. As with everything the better the prep and the better the application the better the results. don't think you can just drop them down on the floor and they’ll be perfect. Be prepared to have sore fingers after working it into all the beads on the floor. The thing with broncos is when you run without a roof or doors the material on the floor isn’t going to help too much. If you do run with a roof and doors do the inside of the doors and quarters and get some insulation in the roof to help really knock down the noise.

 

[jamesroney]

Broncos leak. Here's a picture of 2 different Broncos.

1. 1969 CA “rust free” Bronco with floor mat.
2. 1967 CA “rust free” Bronco with drain holes and without floor mat.

Forget about letting water in. You gotta let the water OUT.

 

[Speedrdr]

Broncos leak. Here's a picture of 2 different Broncos.

1. 1969 CA “rust free” Bronco with floor mat.
2. 1967 CA “rust free” Bronco with drain holes and without floor mat.

Forget about letting water in. You gotta let the water OUT.

There’s actually such a thing as a “rust free” bronco? ? ? The first one I had was a ‘72 that I bought in ‘80. I was the 4th owner and to my knowledge it never had the top off or even had a floor mat and it was rusting through where the firewall met the floor on both sides.

It WAS; however, a MS Delta vehicle and folks there, me included, would go play in the mud and be derelict in cleaning the underside. Leaky or not, they are gonna find a way to rust. It’s almost like the metal used is a rust attracting object…or maybe our rides are made out of compacted rust to hasten the inevitable.
But I digress……..

Randy

 

[67sport]

Looks like we all agree that if it's wet outside your Bronco, it's wet inside too.

Thanks for the tips. The starting plan for now will be dynamat butyl for firewall/under front mat/inside doors.
Is punching a couple of 3/16 holes in the floor boards after dynamat a good idea to assist draining the low spots?
I've got to re-do my headliner, so I'll add closed-cell deadener when I get to that stage.

I like the idea of doing the rear and quarters too, I'm just not sure on how to top that application yet. It's an I-6 truck so not a lot of engine/exhaust noise, and I haul whatever needs hauling in it, so fabric panels will get trashed. Whatever I use back there will have to be function first. I was planning to think on that area after the front.

 

[Wild horse 75]

Just use the same butyl mat from the floors and doors. Just apply it to the inside of the body quarter panels. You don’t need anything to go over top of it.

 

[DirtDonk]

I finally stopped all the leaks in my 71, but it took a couple of years of hunting, sitting inside and watching where the rain was dripping in.
Finally blocked them all. Or so I thought…
A few years later, I was driving down the highway through a driving rainstorm and water started dripping on my legs from the windshield wiper cover!
Turns out that in a heavy downpour at speed, water would get up through the notches that are in the leading edge of the top where the metal is all folded over and a big gap is left.
Filling that and making sure that the gasket is good should take care of that one.
Theoretically…

Got rid of the leaks in the 68 very quickly.
Put one of our waterproof covers over the whole thing!

 

[Speedrdr]

Got rid of the leaks in the 68 very quickly.
Put one of our waterproof covers over the whole thing!

Didn’t that make it difficult though see where you were going??

Randy

 

[DirtDonk]

Nah, the HUD takes care of all that.

Besides, the flapping of the cover in the wind scares the bejeesus out of everybody nearby, so they stay away from me.
Works great as a Halloween prop too.