Hi!
Not sure if this has been posted before but I couldn't find anything in the search. So, I have the awful bottom of the driver's side door rust. It's around the folded part of the metal only on the inside of the door.

I know it is rusting from the inside out from plugged drainage holes. I recently had a friend who is a body shop guy grind off the surface rust and filled it with bondo. He couldn't see down in the crease from the inside but he says it's probably rusty. The outside looks great! Inside of door looks bad.

Just wondering if I could pour some rust converter in there let it sit and then spray a bunch of Fluid Film in after? I can't scrape the loose rust in there because it's really tight. I know rust will always continue but will this slow it down?

Should I spray just the Fluid Film in there? Or phosphorus rust converter first? Thanks!

Cheers,

Johnny

 

I will offer personal advice as best I can.
I had this problem when I first got my ranger. Previous owners had wheeled it alot and I had mud and dirt packed in all the body drain ports. So my solution was this. I first pulled out all the shifty plugs that are supposed to let the doors drain, and left them out. Than I flooded all the doors with warm soapy water with simple green mixed in. I continued to flush all ports and drains till they ran clean. I Used compressed air to get as much water out as possible. I let everything sit for one week without washing it than sprayed them all with electronic contact cleaner because it evaporates all moisture and water. Took 2 cans. Let it sit one day. Than got a a few cans of penitraining oil and flood the passages and bottom of doors. This coats and protects the metal and beads water out. I spray it with oil once every summer now and I have no further rust growth since. I checked this by pulling the door panels and looking in with my scope camera. The problem with a sealer is if you have any moisture whatsoever still there, it will trap it and only make the rust get worse. And you will have to make sure your door drains don't get plugged with it of course.
Anyway, this worked well for me. Hope some of the advice helps.

 

Thanks a bunch for the info W-A! I was going to put the rust converter in first but not anymore.

When I first put it on the surface of the rust it made a really hard iron phosphate 'shell' and I couldn't even scratch it with a screwdriver. It was so solid. This led me to believe the door was good. But when my friend grinded the shell there was so much rust under there, it was all the way through the inner door sheet metal. There was a tonne of red dust that was flying everywhere and found about a 1cm hole.

Lucky I didn't put any of that rust converter in there. It would have trapped the rust under the shell. I'm going to follow your lead and wash, rinse and repeat! ...Then I'll use what we have here in Canada called Corrosion Free Rust Cure 3000. Good reviews.

Thanks again WebsterA!!!

Johnny

 

You're very welcome. I'm in Oregon, so 9 months of rain a year isn't friendly to us either lol.