Fixing rusted out floor pan *UPDATED /W PICS*

[dsio]

Ive been putting my E30 back together over recent months, and knew there was some rust in the floor, but only just saw how bad it really was. From behind the front wheel arch (all four wheel arches are 100% rust free) to behind the driver's seat, there is an inch wide gash, rusted out, down the door cill in the floor pan.

I knock on the floor pan, and it sounds rusted always all the way through to the tunnel. The seat is barely being held in place.

I have access to a professional welder that would work for free and a workshop, but I dont know if this will be fixable. Is there much stuctural importance to the floor pan?

The drivers side is the only side effected.

The pedals and seat rails have also been rusted out.

[Turbo-Brown]

I'd say that the floor is a structural member, serving to triangulate the cills and transmission tunnel.

Think of it this way: Get a margarine tub (an empty one preferably), remove the lid and turn it upside down. This is the car with no floor. Grab each end and twist and it's pretty easy to deform the "chassis". Now replace the floor and give it another go, the whole assembly's much more rigid now (Sorry for putting that in, but been searching for a use for that analogy!)

Anyway, if you can find a car without the rot in a scrappy and remove the relevant bits with a grinder, your mate might be able to graft them into your car.

Lot of work though as you'll have to strip most of the drivers side interior out, especially if the rot extends up behind the dash.

Might be worth going over the rest of the car with a fine tooth comb to make sure it's absolutely worth it first

[pacerpete]

Sounds like you've got a rusty pommy turd mate ,though rusty and all as they get here i haven't seen many with rusty inner sills and floorpans. The only option is to cut the section of floor you need out of a car in a wreckers and fabricate the bits that can't be reused,
Post up a pic of the damage , us poms get off on rust ! . As i said your car surely must be an import that was accident damaged in its murky past.

[A1BMW325iSport]

my old 325 had extensive rust so i bought a donor 325 with good shell but no running gear and swapped all the parts over to that

[dsio]

There are two bits with rust only. The absolute back of the car, in the boot (trunk) below the carpet is rusted through, but it is of no structural importance and has been rust converted, and will be kevlar/carbon fibred soon. Then there is the floor. The passenger side is perfect, and the back is perfect. The area effected goes no further than the pedals, but does include the acclerator pivot hinge. It is probable about a foot squared, but does not come all the way to the cills, and does not go all the way to the tunnel.

It is strong and sturdy, as I have jumped like hell on the drivers seat and surrounding area while a mate watched for flexing, and nothing happened. It still has structual strength, it just is rusting and will soon get much worse I fear.

My plan of attack is to rust convert the entire thing heavily for a start, then to have the gash welded with new metal in the gap, extending over it on both sides, and welding a shim on the underside that covers a large area of the undercariage (a sheet of steel welded up to protect it).

Its holding, and if it doesnt get any worse it will be safe. It looks fatal, but I dont think it really is.

Aside from that the car is a 318i thats done 150,000 KMs (not miles), with perfect gearbox, brakes, running gear, body. The suspension is all good and new, the exhaust has just been replaced, and there is no rust on the guards, arches, windscreen, shock towers, or anywhere else.

It cost around about the equivilant of 800 quid.

[dsio]

I cant afford to buy another E30, as this one was a strech on its own, and I dont want to part it after I have put so much work into fixing it up so far. The engine is barely middle aged milage wise, so I just cant justify breaking it.

I have access to a workshop that does a few things, including a welding school (the guy who teaches welding there would be willing to weld for free) a boat builder (fibreglassing, carbon-fiber/kevlar work) and a full spray booth with professional auto painters. So I can use any of that as a favour from those people, but I cant afford to spend money on it.

[E30Mark]

Well if you've got access to guy who is willing to weld it for free then what's the problem?????

[dsio]

I just want to know if it is something that can be welded successfully or if the welding will just be a temporary fix / bodge job. I know hes extremely good, I just dont know if you can do it to this part of the car and get away with it. It seams solid, so I would assume it would be ok.

Im going to pull the whole interior and take some snaps tommorow, so Iĺl post them.

The car has been in probably 20 odd accidents, but the chrome bumpers have taken all the damage (saved the car in all honesty). No body damage out of it, and I have never dinged it myself ;).

The car did however live on the coast for 20 years near salt water, so its likely the driver went swimming often and hopped her salt watery arse in the drivers seat afterwards. I couldnt explain the location, isolation, and severity any other way.

It isnt an import, as the original owner had it 20 years from new, then a guy had it for four weeks (and in that time destroyed the interior and did some, as they say in england, Ԛ¨chaving it upԚ¨, which I am undoing, and returning to BMW stock), then I got it.

IԚ´ve fixed the SI board, the glove box, the electric mirrors, the wipers, resealed and fitted the spoiler, sorted the gear linkage, removed any junk with Ԛ¨momoԚ¨ or Ԛ¨NOSԚ¨ written on it, and cleaned the interior to very good condition, so I really dont want to lose it.

[Ratfink]

If welding up the floor was a bodge there would be no Ford Anglias left on the road!!

[E30Mark]

You can fox most things with time and money ! pictures will show for show exactly the area your talking about.

I used to weld MG's for fun.... a pome love for rust as pacerpete would say.

[Ratfink]

Look what i've got waiting for restoration!
Some say i'm mad, I say it was Ԛ£300!!

[img][img]http://img400.imageshack.us/img400/562/ ... 0bp.th.jpg[/img][/img]

[E30Mark]

Best of luck!

On my own MG i changed all the floors, sills, boot floor, rear wings, doors, front wings, bonnet, tailgate, chassis leg. The only original panels are the roof, inner wings & transmission tunnel.

I spent 18 months welding it, then 2 weeks after i had finished, Motor Heritage introduced the new body shells but mine is a '67 Mk 1, so even if i had bought the new shell i would of had to transfer the transmission tunnel, and modified the doors & front wings to make it Mk 1 spec.

Glad to say i haven't touched my welder for a few years now !

[dsio]

You can fox most things with time and money ! pictures will show for show exactly the area your talking about.

I used to weld MG's for fun.... a pome love for rust as pacerpete would say.

Lol dont start on those old things. My dad used to restore Austin Bugeye Sprites in his younger years, and we nearly bought one for me until I saw how much rustier it was than this E30. A 999CC engine just didnt quite cut it for me though.

He used to have one of those bugeyes with full burl wallnut dash, and a massively tuned, bored, and stroked cooper S engine with a carb the size of the whole block hanging off it until the rust gremlins took over.

Of the BMWs we have now, this is the only one that has any rust at all. Both of our E34 525is were bought off people that lived on the coast, but are 100% rust free. With English cars, they seam to come out of the factory with some crust on them lol. Adds to the charm.

The sprites lost the scuttle, the floor pans, the door panels, the trunk, and just about everything else to rust, but without the rust they become boring. The rusted scuttle and floor pan means you can smell the oil and smoke from that little 1L 4 banger as it fills the cabin. Such is olden day motoring.

[Ratfink]

aswell as that Galaxie ive got a mk2 consul and an Anglia to do...all need complete restoration.
I like my BMW coz it doesnt need much work!

[Fushion_Julz]

If the floor is *that* strong, then the rust is purely cosmetic...

IMHO, the best route is "if it ain't broke, don't fix it"

Best to remove, treat and repaint the affected panel...no cutting, no welding.

If it deterioates in the future then that is the time to get fabricating/repairing, but leave well alone until then. TBH, if the source of the water has gone away (no more wet surfer bums) then proper treatment and painting will be just as good as a cut n' shut repair

[dsio]

Water can get in from the crack under the car in this panel. It needs to be sealed or at least treated. Ill take the pics in the morning, then coat it all with rust converter to at least halt the progress of the rust. After that, Ill stick a rubber underliner in to keep it dry for the moment until I get the edges cut and welded.

I know water is getting in there because its damp and the cabin has that wet carpet smell to it (I have a trick to ridding it ;))

Thanks for the input guys!

[dsio]

OK, updated with pics now:









Hope you enjoy the rust. It is also around the seat mounting bolts, but not right through, and only very very small. All in all, it wasnt as bad as I thought, and what you see there is about all there is on the car.

[Ratfink]

Cut it out and weld new metal in...its the only way!

[E30Mark]

Oh Rust, rust glorious rust.

I've never seen a E30 rust like that before... has it had a side impact in the past....

Get your welder chappie onto it asap. Make sure he seem welds the lot back together and protect both sides with plenty of paint etc

[dsio]

I believe it has. There is a piece of metal that has been welded into the side in the rear quarter panel on that side, which I was worried about. I took it to a body repair expert that does concourse work and he said the repair job was absolutely brilliant as was the paint. The bodywork and full respray was done around '96.

The panel is perfect (Ive checked inside the door cards on the metal, and they have even powder coated the entire quarter panels as well as rust proofing them after the work, its flawless). But I can kind of understand the side damage having this effect.

I'm going to thick coat it with professional rust converter, and then maybe wire brush the loosest bits of rust and edging that will fall off anyway, and then rust convert any futher exposed bits.

Then I will get it welded.

[Karan]

looks like its been welded before.... and has had another leak and rusted away even more....

reshell mate.... or attempt a cheap fix

[dsio]

A clean new shell is worth more than double what I paid for the car. It simply isnt an option as I have no money to spend at all.

Most of the good shells here have rust in the rear quarters and the wheel arches. This car has perfect arches and rear quarters, which seams to be more important than the floor pan, which is why I am inclined to fix it. If all the rust is cut out, fresh steel is professionally welded, and the whole area is given a massive rust treatment, I dont see how it could be a problem.