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My cj7 has a jeep yj tub swapped by the previous owner. While making patch plates for small rusted areas I noticed there was quite a bit of rust behind the caulking which should protect the tub from rust right? Has anyone else run across this and what did you do? Leave it be or try and remove all caulking and paint again. Would sandblasting remove this?
Caulking prevents water from sitting in the seams, if it is really rusted, the caulking will hold in the rust and rot it. Not sure where you are referring to on the tub? I usually remove the caulking, prep the area (remove caulking, cut out rot, grind, reweld pice in, prime it and paint it, then recaulk it and recoat it after it is dry with herc or something. Sandblast will only remove rust, I remove the caulking with alot of heat, torches til it gets melted and scrap it off with a scraper or screw driver, but I am sure there are some better ways to do it.
I found it was bad along the driver's footwell joining the floorboards to the outside bodywork. Any special type of caulking you use to reapply? Thanks
I found it was bad along the driver's footwell joining the floorboards to the outside bodywork. Any special type of caulking you use to reapply? Thanks

If it was bad there, then you might keep checking other places. I used a propane torch and wire brush to remove all of mine. I then cleaned and primed and ran some more body caulk. Yes use a high quality seam sealer. You can get it in tubes or brush it out of a can. Any body shop jobber should have it. Don't use tub calking or silcone, this stuff is corrosive. This is usually a missed step for many but it really changes the looks of the tub after paint or liner. :2thumbsup:Good luck JC
If someone used RTV or plain silicone as 'caulking', it will eat right through the body metal. It outgasses for years and when water comes in contact with this gas, you get acetic acid that rots metal bad.

The proper stuff is called 'seam sealer' or a Butyl caulk like they use for glass is safe.