Rust remediation recommendations and questions about mystery material

Due to a few leaks in my truck, which I was unaware of, I have quite a patch of rust on drivers side. It looks like I caught it before it had a chance to get really bad... relatively anyway.

I have a few questions before proceeding:

- What is that top layer that separated from the floor, seen in the second photo (my mystery material), and what should I replace it with? it looked to me like a second metallic layer on top of the floor but I do not know what it is and it came off in pieces on the drivers side.
- was it structural at all or just insulation against noise?

- is por-15 rust preventative a good option for this location or would Rust-Oleum’s rust reformer be better?
- other better options for treating this area?

 

I have had this issue but not as severe as in the red Tacoma on the photo there.
Im surprised you didn't smell a dank musky wet floor liner. In any case.

- What is that top layer that separated from the floor, seen in the second photo (my mystery material), and what should I replace it with?

• Are you referring to the material highlighted in yellow? my best guess is its a heat absorbing membrane or some kind.

- was it structural at all or just insulation against noise?

• No, you can peel it off with a plastic spoon, it will reveal the steel body layer highlighted in orange.

- is por-15 rust preventative a good option for this location or would Rust-Oleum’s rust reformer be better?

• You can use either or, the objective is the same. To stop rust from spreading or re-building.

- other better options for treating this area?

• Its up to you, I would remove all the rust, add some kind of tac weld sheet steel and spray paint it white. OR Just remove the rust and spray paint it white. (Why white you ask? its easier to find water, oil, or other crap than black.)
  nothing more annoying than punching a hole thru your cars floor.

 

Thanks for the response.

I did smell a dank musty a couple years back but thought it was just a combination of wet dog, towels, and other stuff you accumulate in the mud mats over a period of 2 months spent out in the bush during mushroom season...
my back got screwed shortly after and it was parked until recently so now it is part of physio. I have a few posts for separate, but related, issues right now.

Yes the stuff outlined in yellow (thanks for the edit) I have done a few searches but have not found out what it is called or what I should replace it with once I am done dealing with the rust.

I am heading out with my dremel and a bunch of mini wire attachments to tackle it in the morning. It looks deeper than it is. I took a large brass brush to it today and there are only a few small troubled spots.

I like the white idea will probably end up installing butyl sound deadening / insulation material after the rust remediation and treatment... I should probably do some before and after pics as well.

Well.. I remember my girlfriend sitting in the back seat of my fathers old 1973 Volkswagen station wagon. She had said something about the floor being spongy and he had said it was just the towel on the floor.. about a half hour later he accidentally drove over a corner of a cement parking curb and took that section of the floor right out. There was a bit of squealing from my girlfriend, quite a bit of laughter from the pair of us after we determined she was not hurt, and a lot of swearing from my father when he realised just how rusted out the floor actually was.

 

The stuff outlined in yellow is a heat/noise dampening material. Search YouTube on how to remove it with dry ice or have lots of painful fun scraping it off. Remediate your rust with wire brush, rust reformer, and then paint over the cleaned up metal, and then just put on your butyl sound treatment layer as a replacement for the OE stuff.

 

This is one of the best youtubes I've seen of rust-converting/protecting coatings. This guy really put in the work testing different coatings over a long time period.

TL;DR for exterior or underbody use, the Mastercoat primer is the best.

https://www.youtube.com/watch?v=TABWPHutk-A

 

there’s rust removing acidic chemicals
And rust converter paints

assuming the floor is intact enough to where if you smack it, it doesn’t break through.

the material is likely sound deadening people remove in race cars to reduce weight. I don’t know if it has other insulating properties such as heat and if that’s important. There’s probably replacements available out there, if not run of the mill dynamat type stuff. That may even better.

whatever comes factory was probably chosen for cheapness and ease of install being mass produced at a factory.

 

Thanks much for that. Very good.

 

Thats my suspicion but it was good enough for me until the water screwed me. Now OCD is taking over.

 

Did you get the leak fixed? What was the source?

 

A real three strikes situation:
- third tail light. gasket gone. fixed with Lexel Multi Purpose Sealant (this stuff rocks)
- rear wall pressure vent ( try push this out then clean around hole with cleaner/degreaser then use Lexel here as well )
- top corner of windshield at passenger side ( pull windshield seal, clean and remediate any rust, pull windshield if I have to, go from there )

No post for the tail light but the other two are here:

https://www.tacomaworld.com/posts/29579131/
https://www.tacomaworld.com/threads/back-wall-air-vent-replacement-procedure.824636/

 

So here is what I ended up doing for the rust. Before and after shot of the worst spot included. (my fixes for the windshield and back wall pressure vent are also in through the links above)

- Disconnected battery.
- Pulled wire harness guides and harness out and worked around them as best possible.
- Took drill with wire brush and nylon abrasive brush to all areas with rust or spots of rust.
- Rinsed all areas with water.
- Scrubbed all areas with CLR and let sit for 30 min.
- Rinsed all areas with water.
- Scrubbed all areas being treated and entire floor area with degreaser.
- Rinsed thoroughly and dried all accessible areas as best possible.
- Put heater and fan in truck overnight to fully dry.
- Took soaked with acetone and thoroughly wiped all areas being treated.
- Sprayed several coats of Rust Reformer over exposed metal / rusty spots.
- Let dry.

My carpet was pressure washed, scrubbed with degreaser / cleaner, pressure rinsed, had excess water removed with wet / dry vacuum, then draped over sawhorse and air dried... sooo clean now.

I still have to remove rust from seats then repaint but I have started putting all the stuff back in.

I will add some follow up pics once everything is back together.