R107 Firerewall / Bulkhead / Plenum chamber rust repair

[berntd]

Hello all

I am new here and have q some questions.

BTW: I am in Australia.

I am going to embark on a major rust repair exercise on my mercedes 1973 450 SL.
I will be using the bulkhead panel kit from the SL shop in the UK.

Can somone who has done this. please let me know if:
1) The windscreen must come out
2) The engine has to be removed
3) The sheet metal between the engine bay and windscreen (cowl) has to be removed to get acess.

There are no instructions available form the SL shop. I did ask.

If anyone has any hints or other information about this, please let me know.


Best regards
Bernt

 

[alabbasi]

I'm guessing that you're going to be welding, will the dash come out? I'd be concerned about setting wiring and insulation behind the dash on fire otherwise.

 

[Druk]

Hello Oz.

Windscreen out. It's bonded so will probably break but at least you get a chance to renew the dreaded trim clips.

Dashboard out. Not too difficult but fiddly and takes time. Does you car have the central parking brake or US style footbrake? If it's the central lever type you start with that and work forward. And you'll need a box for all the little nuts and bolts you're left with once it's put back....hahaha.

Engine stays put.

Scuttle needs cut away for access and heater plenum underneath is likely rusted out as well. Drill out the spot welds along the windscreen flange for a neat replacement job otherwise you'll need a stitch and repair somewhere visible. Not so good.

Heater box out. Good time to renew the foam on the flaps as they give trouble and access is difficult with it in place and to get the matrix pressure tested: otherwise it's dash out again for later repair.

BTW. The SL Shop panel is not the full monty and although good you'll require quite a bit of DIY fabrication to make it fit. It does fulfil the most difficult bits however.


Good luck. take lots of pics as you proceed so you know where it all goes back.

Plenty of further advice on here once you start.

.

 

[grober]

Like most major restorations- and bulkhead renewal is one! - the trick is in deciding just how far to go. Derek^^^^^is the expert who has " walked the walk" with his own car and has offered sound advice. He has said that engine removal is not necessary but you should consider whether this is also an opportunity to check out the front chassis rails, front subframe and its mountings with the engine out??? Just something to consider.

 

[Charles Morgan]

My W114 coupe needed a complete bulkhead restoration but there was also a lot of corrosion in the inner wings where they joined the bulkhead and the front chassis rails, so have a good look in those areas too.

 

[berntd]

Thank you everyone.

I 'll see how I go.

I am having trouble ascertaining the extend of this rust.

WIth the fan motor out, 2 of it's studs are rusted and gone.
Car leaks water into footwells.
I cannot see much in the 2 grille panels. I have opened them but I still can't see any rust.

There is rust (holes) next to where the main loom goes through the firewall. Near the brake booster.

On the left side, I can stick my hand through under the fender into the footwell.
I think that is where the plenum chamber meets the footwell?

Both sills are done for at the front.

I also found holes on the inner fender where the front subframe attaches.

Maybe I have to take the whole thing apart anyway.

This car found me. I was not looking for it as I have tons of other projects lined up.

But I do like it. A lot!
Very first thing is today I will put original baroque wheels on because I hate aftermarket alloy wheels. They prevent me from thinking!


Regards
Bernt