Minor floor rust repair

JHZR2

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This is on my 96 Dodge Ram. The truck let some water in, I knew that when I bought it. Neither door had a vapor barrier for whatever reason.

I pulled the lower trim, and noted that some screws were missing. When I pulled it, I saw a couple holes where the screws were, and some rust, like water had gotten under the paint. I pulled the rubber mat and sound insulation further in, and it’s solid and the paint is fine. It’s just along that strip where I guess water sat, there were some seams and openings due to the screws that went through, and it has eroded things over time.

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I’ve left it open for a few weeks now, and watched it closely, including with hose spray, heavy rain, etc. no water gets in anymore. I’ve sealed out the water fortunately.

So now it’s time for stabilization. Because the metal further in and out is generally solid (there are a few bumps in the rocker, but they are solid, FWIW), I’m hoping to stabilize it for now, and think about it from there. It is a 25yo truck with 441k miles.

I’m thinking of the POR epoxy or POR patch paint, which may be the best bet because it’s thicker, dries hard, waterproof, and will bond very well.

I’m not opposed to cutting some metal out and trying to learn wire welding on this. But I’m not sure if this will be overkill and overboard. The rust shown doesn’t seem to substantially compromise the metal. Hammering or trying to puncture isn’t successful. At some point more detailed rust removal may be prudent, but for now I just want to get it stable and covered so humidity and rain from my feet (and up through the holes, which I’ve not seen, but could be possible, at least via humid air) so it doesn’t get worse or spread into more good metal.

So what would you use to at least stabilize what is seen there?

Thanks!
 
I dont see a lot of good metal to mig new metal onto. Whats it look like from underneath? Any metal good enough to mig a long patch against? If so do that and then wire brush the top and pour por 15 all over it.
 
I dont see a lot of good metal to mig new metal onto. Whats it look like from underneath? Any metal good enough to mig a long patch against? If so do that and then wire brush the top and pour por 15 all over it.

The underside has a couple small bubbles, which I knew when I bought the truck. I was planning on buying it and running it for a few months just to get through some construction I was doing, but it has grown on me. At least to get it to 500k miles.

So it feels solid pushing downward on it, it feels solid pushing upward from underneath, except at the bubbles.

I don’t have and don’t know how to MIG weld. I would be more interested in learning how to use a wire welder. Is that not the right kind for this?

I suspect if I cut back to the rocker, and just a few inches inboard, I’d have solid metal. The issue is that getting to the rocker is a vertical riser that the door seal rides on. It wouldnt be a huge patch. The riser itself (under the door seal in the picture) is solid and sound it seems.

I wonder if a strip of gavanized, in a POR sandwich under and over it, and pop riveted in at points where there is good metal and in between would strengthen and seal it. Seems like a hack job, but it may be good enough for this for what it is, especially given that I’ve resolved the water entry. But I have to wonder if there’s benefit to that sort of thing.
 
I have found POR-15 and POR patch to work and hold up well. I've been impressed with how tough the coating is.

I don't live in road salt land though.
 
That doesn't look minor to me. The only fix is cut out and replace the rusted metal with new.
I agree. Unfortunately any coating, rust converter, filler, etc. is band-aid at best. It all boils down to how long the OP plans on keeping the vehicle.
 
If I were going to keep the truck for an extended period of time I would cut out the bad, buy an outer floor pan and use what I needed of that to repair it.
 
Like you say, I'd try to clean, prep and apply some type of rust converter product. The other avenues just don't seem worth it for a 1996 Dodge.

I tend to agree, the cost to procure significant welding equipment to do major repairs on a 25yo truck closing in on a half million miles to me seems like folly. I like the truck, I’ll put more miles on, but it’s not a dd or show truck.

I have found POR-15 and POR patch to work and hold up well. I've been impressed with how tough the coating is.

I don't live in road salt land though.

I suspect it has much to do with the quality of the bond and the exposure to moisture. I think the issue here was holes (OE) drilled through the floorboard, which allowed standing water to creep under the paint, and lift it. The damage is actually very narrow in the channel Ive photographed.
That doesn't look minor to me. The only fix is cut out and replace the rusted metal with new.
Everything I’ve pulled up has looked ok except that channel.
It’s actually only the channel I photographed. The area is an inch wide and a few feet long, with all but the holes still “strong” (fwiw). The holes are where the trim was screwed (OE) through the floorboards, and where the water could reach the exposed metal and get under the paint. The water was just in that channel (fixed), and drained out the holes, which is why it’s limited.

I agree. Unfortunately any coating, rust converter, filler, etc. is band-aid at best. It all boils down to how long the OP plans on keeping the vehicle.

I bought the truck with the intent of heavy use for a few months then unload it in a more lucrative market than middle of nowhere PA. It runs so well it grew on me, and I’ll put the next 60k on to get to 500k miles. The truck doesn’t even have to live outdoors if I don’t want it to, and won’t see road salt from me ever again. It’s a 2wd used for sonstruction that I’m doing personally on properties I own, as hobbies essentially. No need to go out or use it when I don’t want to.
If I were going to keep the truck for an extended period of time I would cut out the bad, buy an outer floor pan and use what I needed of that to repair it
I wouldn’t be opposed to learning to wire weld and putting some new metal in the channel. It’s probably a $500+ investment regardless of if I DIY and try to learn, or have someone do something. The rest of the floors seem ok.but I have to wonder if patches made out of cut 22-18ga (whatever matches) sheet metal woukd do as well as buying a floor pan. Just grind to bright metal, stitch in, paint, etc.
 
I got it now. It might be a great truck to learn how to weld, etc. if you desire. A quick band-aid would be a rust converter, maybe a coat of POR-15, and a blast of something like Amsoil HD Metal Protector and call it a day. It would probably slow down the corrosion a bit.
 
I suggested an outer floor pan, which can likely be had for under $100, because of the bends and contours. It will save you the time and frustration of bending and pounding a piece of flat sheet into shape.
 
I'm about as far from a body work expert as you can get, but I still think trying to cut into and replace metal in this area on a (I assume) rust belt driven 25yr old Dodge is going to open a can-o-worms.

Trav has posted up excellent suggestions and products in regards to cleaning up, slowing and/or fixing similar situations in other threads.

The only conversion products I have some experience with are POR-15 and Rust Bullet. Both worked well for me.
 
I got it now. It might be a great truck to learn how to weld, etc. if you desire. A quick band-aid would be a rust converter, maybe a coat of POR-15, and a blast of something like Amsoil HD Metal Protector and call it a day. It would probably slow down the corrosion a bit.
I like the concept of learning to weld on it. It’s inside the cab, easily hidden, not too big, etc.

I do fear the process to find bright metal, even if it all feels solid... if it results in lots more removal, dealing with seal bolt down spots, etc., all of a sudden a great power train might be condemned. I wouldn’t want to try to weld to rust, so it’s tough.

maybe a little time with a wire brush is worth it to see where things are at a bit more, then be very fast to cut bait... and move to por patch....
 
I respect the desire to turn this into a learning project, but my fear isn't so much the body work, it's putting the time and effort into it, only to have something else send the truck off to the bone yard. The old everything ages at the same rate thought process.
 
I respect the desire to turn this into a learning project, but my fear isn't so much the body work, it's putting the time and effort into it, only to have something else send the truck off to the bone yard. The old everything ages at the same rate thought process.

Yeah me too. All it takes is one thing...
 
I like the concept of learning to weld on it. It’s inside the cab, easily hidden, not too big, etc.

I do fear the process to find bright metal, even if it all feels solid... if it results in lots more removal, dealing with seal bolt down spots, etc., all of a sudden a great power train might be condemned. I wouldn’t want to try to weld to rust, so it’s tough.

maybe a little time with a wire brush is worth it to see where things are at a bit more, then be very fast to cut bait... and move to por patch....
No harm in testing the waters with a wire brush. I would say tread lightly. I've opened Pandora's Box a few times with a scraper and wire brush, and ended up with a project I didn't plan for. Having said that I learned a few tricks along the way. It's nice starting out on a low stress project were an OK job is perfect.
 
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