Seam Sealer FJ40 Cowel (3 Viewers)

[DaveyB]

Hello fj40 friends,

I’ve done a full bare metal restore on an 1974 fj 40 and have come to a dilemma in the paint and body work.

The entire vehicle is primed and ready for paint, the only thing I haven’t done is the seam sealer.

My question, is seam sealer necessary? I’ve shot primer down into all the seams and there’s no bare metal anywhere. I almost think the seam sealer could create further problems by cracking. I’ve ordered a 2-part seam sealer but wondering if anyone has skipped that step and if it’s actually necessary with the proper metal prep.

Thanks!

 

[45Dougal]

Auto manufacturers use it for a reason.
Unless you've submerged it in paint, there will be bare metal in there somewhere.

To misquote jurassic park... "Rust.. finds a way"

 

[DaveyB]

Auto manufacturers use it for a reason.
Unless you've submerged it in paint, there will be bare metal in there somewhere.

To misquote jurassic park... "Rust.. finds a way"

I guess I should add, I don’t plan on driving it in harsh weather, and it had 4 coats of primer sprayed.

But, there’s always the car wash sneaking some water down in there.

 

[DaveyB]

A photo

 

[45Dougal]

I guess I should add, I don’t plan on driving it in harsh weather, and it had 4 coats of primer sprayed.

But, there’s always the car wash sneaking some water down in there.

Personally, I'd wait for a bone dry week, and then seal the heck out of it.
The last thing you want is a teaspoon of water bursting a seam open with rust

 

[tstepp920]

What type of seam sealer do you guys recommend for the body? For the rain gutter and cap?

 

[pb4ugo]

I guess I should add, I don’t plan on driving it in harsh weather, and it had 4 coats of primer sprayed.

But, there’s always the car wash sneaking some water down in there.

Plans can change. I watch the weather too, but a threat of an isolated thunderstorm isn't going to limit me from driving the 40. I've seen a number 40's in the past where the glove box was severely rusted or water was leaking thru that seam and on to the floor. I would certainly seam seal between the cowl and windshield. When you wash the 40 water will get into that seam if not sealed. I've recently had to repair the rusted bottom lip of the windshield frame under where the w/s rubber gasket seals the frames channel.

 

[SteveH]

I would use sealer on the cowl, as it's so critical and exposed. I skipped it (well, added later inside) on the side seams, discussed here: FJ40 side seam - fill with seam sealer or not? - https://forum.ih8mud.com/threads/fj40-side-seam-fill-with-seam-sealer-or-not.1355402/

 

[rlong]

in addition I seam sealer it look long term. Dirt or even rust from older open seams IS a thing.

 

[SteveH]

I squirted oil/grease down my 'open' seams (sealed from the back side) and my truck is somewhat of a garage queen. I'll get plenty of warning if rust starts. Colorado's humidity tends to be friendly in this regard.

 

[diesellibrarian]

Seam sealer is terrible stuff to work with, and it tends to get everywhere. I've found my results improve dramatically with careful masking on either side of the seam. Then you can run a (gloved) finger along the seam, pushing the sealer in and leaving a nice smooth finish that looks factory. Remove tape, and yer done!

 

[anothernz45]

Sounds counter productive but I masked up as above, then used a damp lint free rag over my gloved finger. Just find a new clean bit as you go.