Really need some help here guys. I have an 81 300D and would hate more than anything to see it go, but just recently I noticed rust on the floorboards by the outside back corner of both front seats. Hopefully the pictures I'm attaching show up. I'm just hoping for your guys' advice on whether this is a repair I can manage myself(I'm not a welder), or if I can't, how expensive of a fix am I looking at? I know that it's rusting in probably the worst possible place. Thanks for any help.

First two pictures should be view from inside the car behind the driver seat, you can see the road through the floorboards here. Last picture is from the bottom of the car.

I know it's in bad shape but the engine runs beautifully so I'm really hoping this doesn't put the car at junkyard status here.

Attached Thumbnails

     

Suprising to see that much rust in your region. If it is localized and not spread it can be addressed.


It may have been just two areas indulated with moisture. I would probe around to establish the limit of the rust. Floor pans are available but you must have solid metal around the perimeter to weld them in.

Agree with barry, i would pull the seats and carpet and assess the extent of the rust. I would say from the pictures you've posted that you should probably have that welded. It is a structural part of the car, and since the seatbelt buckle is bolted to the seat, you especially want to make sure those parts are structurally sound.

You can buy rust-repair panels at several places, such as millsupply.com, and they sell floorpans. As far as cost, I would try to find some local shops (autobody, welding shops) that would be willing to weld the pans in for you. If you find a place that is willing to let you prep the car (by pulling the seats, carpeting, wires, etc. from the rust areas) and supply the panels, and just pay them to cut out the rust and weld in the new metal, that would help you save some money.

This would be a good time to also check the car for rust in other common areas, such as behind the front fenders, other parts of the floor, etc.

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"Senior Luna, your sense of humor is still loco... but we love it, anyway." -rickymay ____ "Your sense of humor is still loco... " -MBeige ____ "Señor Luna, your sense of humor is quite järjetön" -Delibes

1982 300SD -- 211k, Texas car, tranny issues ____ 1979 240D 4-speed 234k -- turbo and tuned IP, third world taxi hot rod

2 Samuel 12:13: "David said to Nathan, “I have sinned against the Lord.” And Nathan said to David, “The Lord also has put away your sin; you shall not die."

I had a little rust in the rear right footwell. After I pulled the seat and carpet, it was important to scrape/peel off all the sound deadening material as well - and you have to keep ripping that stuff off in all directions until you stop seeing rust. Luckily, my area was fairly small and didn't compromise the seat mounting points. I ground away all the rust to bare metal and treated the area with POR 15 (I pre treated with cleaner and etching I think too - there is a 3 part kit that POR sells). I also built up multiple layers of fiberglass cloth cut to size and soaked in POR 15 to cover the small holes. That may be a trick I learned from our friend Ken, but honestly that stuff is crazy strong when you build up layers (I'm not saying it would stand in for welding new metal of course). On the underside, I also ground to bare metal, treated with the por 15 process, and then covered the wound with a 3M urethane seam sealer. I check the area often for new moisture/water buildup. It's doing well, but of course - everything on this earth will decay at some point you can only delay the inevitable.

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Andrew
Montclair, NJ
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1982 300D Turbo
120k
Petrol Blue Green

Search for a chassis builder/fabricator in your area. That repair needs to be strong, not pretty. If there are any racers in your area they will know where to go for this type of fabrication and welding.

They will probably do the job if you thoroughly remove all carpet and interior pieces surrounding the repair area. They don't won't want to do that and you probably wouldn't want them doing it either, it's costly from a time perspective.

Good luck!!!

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"Rudeness is a weak man's imitation of strength" - Eric Hoffer

Here's where that's headed:



If you can't get the pans professionally welded, it's time to give it up.

I have done this repair several times now on 123s. An earlier post mentioned that this should be structural because the seat belt rides on the seat. That is true, but in my experience with rust in that location, the seat belt where it attaches to the inner rocker is also compromised. If its rusted out below where the belt attaches, it will need to be welded to be safe.
If the metal around that seat belt attachment point is good, I would say you can get away with por 15, sheet metal, self tapping screws, and some kitty hair fiberglass. Clean it up and find the maximum extent of the rust, put several coats of por 15 on it. It looks like the seat mounts are completely loose, if not tear them out, clean and por 15 if they are solid enough to reuse.
In order to be strong enough to hold the seat, you will need to bend the sheetmetal and screw it to the inner fenderwell (in front of the seat belt bolt hole). Then bend it into place and screw it down as best you can. You will need to screw the seat mounts to this new metal so you have a place for the seat to mount.
Once you have it as best you can, use the kitty hair fiberglass to waterproof and seal it from above and below.
Bolt your seat in and go, or cover the whole repair with undercoating for the "professional look".
The above is redneck body repair 101. For a more authentic redneck look, substitute sheet metal with license plates, and the kitty hair fiberglass with caulk. I would caution against that, though as license plates don't last long as structural components.

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1985 300 TD 448K
1984 300 TD 278K

1983 240D euro 240k
1994 f-250 idi turbo 330K
1986 f-350 IDI
1987 F-350 IDI

1985 JD 1050 4wd
1965 IH 3660

I should note for both the OP and any reputation I might have on this forum, I generally do this repair well welding in new metal. I have even fabbed up new seat mounts. I have also done the above shortcut to keep beaters on the road.
To the OP, if you have someone weld, make sure they know the undercoating ignites when you weld on the floorpans and they may not notice if they are welding from the inside. It can usually just be blown out if noticed early.

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1985 300 TD 448K
1984 300 TD 278K

1983 240D euro 240k
1994 f-250 idi turbo 330K
1986 f-350 IDI
1987 F-350 IDI

1985 JD 1050 4wd
1965 IH 3660

Did you find out where the Water that caused the rust was leaking in?

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84 300D, 82 Volvo 244Gl Diesel

Alternative to welding for minor floor rust:


remove any loose rust, wire brush
treat all rusty metal with phosphoric acid based metal prep like ospho - let sit 24hrs (follow the directions)

get some 2:1 laminating epoxy resin that takes 30min or longer before it "gels". There are a lot of good epoxies today, just get one that isn't too viscous and has a good working time.

get some fiberglass matting (cheap). Break it up and use it to fill and cover all the bad metal.
Tape off any holes that may drip through.
Saturate the fiberglass fibers with the freshly mixed epoxy (make sure all air bubbles are out of the fiberglass before the epoxy thickens up).

Wads of the fiber/resin can be shaped to fill and cover all the bad metal.



Only use enough epoxy at a time that you can work into the fiberglass matting before it kicks off. Alcohol works good to clean any uncured resin up if you get it on your hands.

Make the epoxy/fiberglass layer(s) thick and it will be super strong and seal the metal off from any future rusting.

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1985 300TD 1981 Scirocco 1.6D conv 1986 Golf 1.6D 2003 Golf TDI

I have done this numerous times using heavy aluminum, roofing cement and screws. The car value will not support a full on welding pan repair. Too many hoses, brake lines, e brake cables, wires and fuel lines too, not to mention setting the undercoating on fire.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Thanks for the advice guys! I have a friend with welding experience coming to look at it in a couple of days to see what he thinks. I'd definitely rather have it welded than pieced back together with epoxy/fiberglass/etc.

That's insane! There's more road than car in that picture! Is this in the same area of the car or somewhere else?

It was under the passenger seat.

I may have found a good bodyman in middle TN. He says $50/hr and sent me a pic of a current hood that looks like glass. He currently has my 85SD and I'll soon have confirmation of quality and reasonableness of total cost. (My test job is relatively small with a stop limit because hourly can run into more than it's worth.)

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85SD 240K & stopped counting painted, putting bac together. 84SD 180,000. sold to a neighbor and member here but I forget his handle. The 84 is much improved from when I had it. 85TD beginning to repair to DD status. Lots of stuff to do.