Ah ********... Rust mitigation advice needed.

[RyanUsesThis]

I was hoping my first thread here would be my overall build thread, but I'm going to need some advice on this one. While sanding down the bed of the van for a POR15 treatment I came across a bubble. I broke out the angle grinder and to my dismay, sanded down to straight up rust.



The rust is right over the support beam between the rear wheel wells, and is not accessible from the underneath of the van. It's also right next to the main bolt holding the van body to the frame. Obviously the only way to deal with this is to cut the rot out and weld in a clean piece of metal, but how should I deal with this seeing as this is such a structurally sensitive area?

I cut into the metal as far over as I was comfortable, and it looks to me like I'd be cutting out the metal surrounding the bolt...



Has anyone done anything like this? I'd prefer not to destroy my van after sinking a sizable chunk of cash into a 4x4 kit

 

[pugslyyy]

Can you remove the bolts enough to lift the body up an inch or two?

 

[45Kevin]

If that is the only rust on your truck, you're golden.

Poke a screw driver through the hole to remove as much of the rust as you canreach and then spray it with a rust stopper/converter.

You can weld a patch in the hole or use some fiberglass if you don't weld.

Or, you could remove the body from the frame and totally treat your frame to a sandblast or wire wheel. And then weld a patch in the hole.

 

[RyanUsesThis]

I would love to pull the body off and take care of the rust properly, but I don't have the means to lift it, and i'm guessing it would be cost prohibitive to have someone else do it (has anyone done this? Estimate on cost?). I can remove the bolt at the very least, and cut out the metal around it and weld in a new peace for it to go through.

I'll be glad when the rust mitigation portion of this project is over. I just spent two evenings under the van prior to this spraying the entire undercarriage and drivetrain with Fluidfilm... Everything smells like minty, peanut buttery sheep now

 

[Paddy]

Por15 is neat stuff. It soaks in and really seals thick ugly rust. If you want, you can drill a small hole or holes above the affected area, and literally pump or pour the stuff in and let it drool over the rust internally. It will harden to a rock hard and sealed substance. Bondo it up and you're good for at least a decade.

 

[RyanUsesThis]

I stared at that rust and the area around it for a good long while. The biggest issue I had about cutting the floor out was that when I got the van it already had a 4" hole cut in the bed for "an air conditioner vent"... I patched that up with sheet metal and rivets. If I were to cut the floor out for the rust I'd have to go around the original patch, and so would end up with a hole in the floor roughly 12" x 13"... ad to that, I only have a tig welder, mediocre welding skills, and a van whose undercarriage is covered in fluid film. Not a good combination for trying to weld 16 gauge sheet metal.

In the end I cleaned out the hole the best I could, and just poured the POR15 in. It seeped through and started dripping out from under the van, so it definitely spread it's way around in the effected area. Crossing my fingers it holds up :\

I'll probably hit it with another coat, and then fill in the rest with some sort of epoxy. As for the other side I'll be giving it regular blasts of Fluid film. Hopefully that'll be enough.