Hey y’all, I was going to undercoat my xj. Current looks of it aren’t terrible but there are definitely some tlc it needs. I attached some pics of what it looks like currently. It has the original undercoating and paint still on it but I live at the beach and want to prevent anything down the line

what I was going to do:
1: air needle everything down and sand
2: apply degreaser to clean, pressure wash and let dry
3. apply Rust Kutter then dry and pressure wash
4. apply rust reformer paint from rustoleum
5. Apply B’laster surface shield

I have a air compressor and would spray it through a air gun in the frame as well. Besides the rust reformer that can in cans

thoughts?

 

Sounds like a good plan! My rustproofings of choice are CRC marine corrosion inhibitor and fluid film.

 

I like your plan

I live beside the ocean over 50yrs.

You can only have too little rust prevention, never too much

Spray inside things (including uniframe) using an air gun with long nozzle, they are made for the job and very cheap

Go insane, the inner pillars, inside doors, the XJ allows for it

Yours appears to have some corrosion. I would examine those areas for possible repair, as once red rust forms, its hard to stop, depends on how serious you are about keeping it

 

Bringing this thread back for some additional input.

I'm currently refurbishing a 1995. It also has the same gray looking factory (?) undercoating. I just dropped the gas tank and rear end to do a rear suspension upgrade.

I needle gunned a little area of the factory undercoating. It came off fairly easy. It was pretty brittle but it was hit with a needle gun. I think I will try to get as much of the original stuff off then coat with primer and top coat. Something like a Rustoleum Farm and Implement enamel. I would finish with a fluid film/oil based "undercoat" after it's cured.

I have a good amount of rust to address. The rust is getting cut out and new metal is going in. I want to protect the good metal as best I can.

Basically looking for thoughts on whether getting rid of the old stuff is worthwhile. Or should I just leave it and Fluid film it religiously?

 

My understanding is there is a factory zinc coating on some surface under the paint, dont remove that if not rusty

inside the frane and rockers should be completely washed out. if there is some rust, consider a phosphoric with zinc treatment. Inside rockers and frames can be hard to paint, spray guns with wands, and holes drilled can deal with this, assure you dont paint over thick acid residues.

A great primer is Du Pont DPLF available in several colors, it is a two part epoxy, extremely good adhesion. use at least two coats, then top coat in a good enamel if you want a pretty color.

use of fluid film is a nice finish touch considering a salt enviroment

Dont forget the top of the rockers that is hidden under the plastic sill plates, and very important is inside the door bottoms, and the seams on the door where the door skin is crimped onto the doors frame structure.

Also consider inside the engine hood as that is a double crimped layer, the outer skin over the frame, clean, paint and or fluid film around the hood perimeter on inside.

Later hatch back doors are steel, so again deal with the crimped seam. early hatch is fiber glass

The door hinge area tends to rust in the A pillar, and the B pillar in four door models use of fluid film in the pillars around hinges is good idea

Assure the rain gutters have good paint, there is a seam there. if the paint and seam sealer crack, rust can take hold there.
I am not a fan of the thick rubberized coatings with tend to trap moisture, and hide rust until the rust becomes horrible.

good luck

 

Decided to remove the original undercoat from the frame (uni-frame) and other structural and areas that were rust questionable. I did knock down a lot from the underside of the body panels but it was still adhering pretty well. It came off the frame pretty easy.

After I'm done with needle gunning/wire brushing I'm going to give a good cleaning and wipe down with mineral spirits and apply a good primer and top coat.