Foam between inner and outer fender??

[Scottcorvette]

There was a foam strip between my inner and outer fender, I guess either as a splash shield or to prevent vibration/drumming. I think this was pretty much responsible for the rust between the two panels as I would think it retains moisture pretty badly. Corvettes had a similar thing on the chassis rail and they are often rusty underneath this foam strip. We normally leave these off.

I was going to leave this out when I fitted the new fender so as to avoid any problems like this in the future. Ha anybody left this foam strip out and suffered any drumming from the rear end bodywork or any other issues?

It is unlikely that this car will ever see a wet road unless by accident, certainly during my ownership so I doubt it would be that much of an issue if I did reinstall it, just wondered what the general opinion was?

[Shvegel]

My car when it was new to me had rear wings that were brazes on with no foam.  No drumming from the body.  The way the metal is shaped around the wheelwell I can’t imagine it would.  I would guess that strip was there to keep any acumulated dirt from packing up down in the crease and causing rust.  Which of course means the strip actually made it worse.

[Scottcorvette]

Thats kind of what I figured, I just didn't want to make a mistake and then have someone tell me that it was common knowledge the foam had to be in place. It didn't seem like a good thing but noises in cars can eminate from some strange places. I noticed there was a small square of sound deadening material on there which I will apply again.

I was going to use a thick bead of this between the two panels:

https://www.3m.co.uk/3M/en_GB/company-uk/3m-products/~/3M-Polyurethane-Seam-Sealer/?N=5002385+8709313+8709338+8711017+8711413+3293211317&rt=rud

But it can only be welded through within 35 minutes and I don't think I'll be able to get it on and all my spot welds on in time. I'm used to working against the clock whilst fitting panels, Corvette panels are bonded on and you have around 5 minutes work time to glue a panel on before the bondo starts to set. It's a horrible experience and I don't feel like giving myself that added pressure with this car, it's stressful enough as it is!

I think if I attach a long nozzle to the seam sealer tube and get Ronni to help me I should be able to squeeze a bead in to fill the void between the inner and outer arch.

[Shvegel]

Good luck.  When I redid the mechanicals 16 years ago I figured out that the car had a “pace” that it wanted to go and any additional effort on my part to go any faster just resulted in the same forward speed and additional frustration.  I was a line mechanic at that time and when the day was over I put away the air tools, took of the rubber gloves, took a deep breath and went to work on the Mercedes.

[Mike H]

Hi Scott.
I have a 64 230 SL and have replaced the outer wheelhouse with the outer fender in tact.
I mig welded the wheelhouse, first tac welding the vertical seams in the join at the centre of the wheel space, then welding the entire join front to back, painted the car, stone guard and more paint.
The joint sealer I have used when replacing the floors and other panels,BUT, always poured fish oil into the seams (panel laps) at the end of the exercise.It is the reason I believe my car will be rust free in another 50 yrs.

I found a rubber gasket in there as well. No idea why.
The drain holes for the channel that houses the seal for the soft top lid dump water into  your problem area.Bad idea.
I have drilled numerous 19 mm holes into all closed box sections for spraying fish oil (which can be repeated) and sealed them with rubber blanking plugs, and screwed in self tappers at the low points to drain excess oil.
I,ve used stainless screws on rebuilding the car and dipped every screw bolt in fish oil before fixing . This lubricates the thread, seals the thread, when dry acts as a Loctite, prevents rust,and guarantees you will always be able to undo the bolt.
Cheers,
Mike.
Feb 64 230 SL RHD Auto .Both Tops.