Fender to Shroud Joint

[vette]

Hello Everyone, On the fender to shroud Joint, did the factory install any kind of a gasket or non-corrosive membrane to keep the aluminium shroud from direct contact with the steel fender. And is anything available today to replace it. I'm in the process of hanging fenders on my Healey now and my car had do such membrane there when I took it apart. The fenders are new and the shroud is in good shape, thank god.
Cheers, Dave C.

 

[GregW]

Hi Dave,
The factory had some sort of caulk like stuff smeared in there. Moss sells a joint strip that I haven't tried HERE #87 if the link doesn't sent you down to the bottom of the page.

 

[Randy Forbes]

Honestly, with todays epoxy-type primers and paints, combined with minimal poor weather driving and likely non-existent winter (read SALT) use, I wouldn't worry too much about electrolytic corrosion.

My car was sourced from California, and when I took it apart thirty (30) years ago, there was no <span style="font-style: italic">barrier</span> protection evident, nor any corrosion on the shroud flanges.

 

[GregW]

My car spent most of it's life on the East coast, more humid and rainy weather. The first shot shows the barrier putty, the kind of black cracked crud. The second shot show aluminum oxide where the speed nuts from the fender rubbed through the paint.

 

[healeynut]

Seems to me good old bog standard zinc plated speed nuts and bolts is the way to go, maybe powder coat them for extra measure if you want.

 

[GregW]

Yeah once those speed nuts rust, they turn into little sanding blocks.

 

[vette]

Thanks Everyone, I will look at the product from Moss. I also thought maybe the layers of paint products that will be on there might be enough. But since I'm anal about almost everything I was looking for something more. I have one other idea, that is to use some sort of tape, maybe even just masking tape. Tape the shroud flange when I final hang the fenders, after the fenders are fitted up to the car real tight, then use a utility knife to slice off any exposed tape. then epoxy seal the whole car and bury any tape edge that might show. This would also ensure that no moisture would penetrate the tape edge. the only issue is, at what point do you put the beading back in place? Having said that, maybe the answer is to do the epoxy paint with the fenders off, and do the final paint job with the fenders just gapped a smigen.
Dave C.

 

[Ed_K]

I used the moss product while installing the wings. It is like a thick tape but made of a sticky rubber like substance. It was not difficult to use so If you are considering a tape, why not use the moss product ?

 

[Jerry]

I was just talking to Martin Jansen (Jule Products) who makes replacement frames for our Healeys. He says there was noting used from the factory and if you do use a sealant, there is no place for the water to get out so it accumulates and causes dirt and crud to get stuck in there. He also agreed with the previous comment that modern paints are a good seal for the corrosion. Of course, if corrosion were a big issue, it would be apparent where the bolts go through the fender and shroud.
Based on his suggestions, I am going to leave the joint naked.

(that just sounds weird)

Jerry

 

[GregW]

Well Jerry, I pretty much have to disagree with everything Martin says.

...He says there was noting used from the factory...

I know the full history of my car and mine came with it. Maybe it was something introduced later in production.

...if you do use a sealant there is no place for the water to get out so it accumulates and causes dirt and crud to get stuck in there.

In that tight a crevice, water isn't going anywhere anyway. Water tension will hold it until it evaporates. Whereas the joint seal, if properly applied, would keep the water from getting in in the first place. Of course, the SS beading will help block some water from entering.

...Of course, if corrosion were a big issue, it would be apparent where the bolts go through the fender and shroud.

I do agree with this as evidenced by the corrosion in my photo above.

...I am going to leave the joint naked.

(that just sounds weird)

Jerry

Yes it does. :laugh:

 

[vette]

In in talking with some local people as well, it seems there is some shared opinion that the paint layers themselves are enough to protect it. Remember electrolytic action between steel and aluminium doesn't need water to help it along. the evidence is that most shroud edges you see have deffinately shown deterioration. I do believe that the factory had something in there to sparate the two metals. I think Greg,s is pretty close to the evidence of what was probably there from the factory. so the question is what do we do about it.
Moss does provide a product for this application. An yes as per ED K. a tape could be used. But I do believe a tape will trap moisture, etc. to expediate deterioration. So I'm back to my original premise, to tape it with something rather thin and bury it in a good coat of epoxy ( I do not believe the tape will lift causing later issues because the tape will be tightly trapped in the joint); or let the layers of paint do the protecting. ( there will be epoxy, 2K urethane primers, multiple coats, then colour, then 2 to 3 coats of clear). The urethane products, are resistant, thick, and virtually indistructible. BUT!!!
where you bolt up two pieces of metal tight and have bolts going thru, you could rub thru paint. I think once the fenders are bolted up well they won't be moving around and will not rub thru.
CHEERS, Dave C.

 

[GregW]

Hi Dave,
The one thing I'll mention about tape, is the non-stick surface it has (otherwise, you'd never be able to unroll it). Paint might not adhere as well as painting directly to metal (or primer).

 

[bob hughes]

Just taken my rear wing ( fender) off. The car has been restored in the past, nothing in the joint and as it was re-painted in pieces the edge of the shroud looks brand new with the very minutest of aluminium oxide in the area of some of the speed bolts. Worse corrosion down at the rear of the cill ( rocker) level - a rusty hole. I have considered using a seal on replacement, but if everything is painted before assembly ( this may not have happened at the factory ) then that should be good for another twenty years.

Now faced with door and front wing removal to get at the cills for replacement.

Bob