TR6 TR6 B-post to inner sill connection

[alphatopher]

I'm in the process of installing new floor pans but I need to first address the lowest section of the b-post where it connects to the inner sill. The outer sill and floor pan have already been removed. I don't know if this was original or not, but this connection between the inner wheel well, b-post, and inner sill was packed with some kind of putty to prevent water intrusion from the wheelwell. Well the putty failed and resulting in rust in this pocket requiring the replacement of the lowest section of the B-post and some of the inner sill.

Should I patch weld the post as best I can then pack it with putty, or would it be better to re-engineer by welding a more effective joint which would drain water rather than collecting it. Any ideas would be appreciated, what have you all done to fix this area.

Also, how do you determine what is an acceptable amount of rust on the B-post seat belt nut? The nut isn't rusted but there is rust of the reinforcement plate that the nut is connected to. My plan was to remove the scaling rust then POR 15 it.

 

[Adrio]

I can't speak to the specifics of the TR6, but for my TR4A (and in general) I took the approach that I can't keep all the water/moisture out, so I make sure there is a way for it to get out and get dry.

 

[Alan_Myers]

Hi,

I agree with Adrio, there is some condensation inside even a closed and sealed section, so some sort of drain provision is a good idea.

In addition, a separate 1/2" access hole might be a good idea, to allow Waxoyl or similar product to be sprayed inside the area, after which the access hole should be closed up with plastic plugs available for that puprpose.

I think the B-post on most TRs are vulnerable to splash from the rear tires, then tend to rust toward the inside of the car once the water and mud finds it's way inside. It also didn't help that the inner fenders and lips on the outer fenders often only got a thin, cursory coat of paint. The easily removeable outer fender design of the cars makes that entire seam vulnerable. Even someone with a totally rust-free car would be wise to remove all four fenders and spray the insides with a good rust preventative paint. I did this with Rust-oleum red primer on the front fenders of my TR4 in 1979, and there is absolutely no rust inside that area today (even though I wasn't clever enough to reroute the scuttle drain at that time). The car was on the road for a number of years after that "rolling restoration".

At the rear, though, I simply sprayed a heavy layer of undercoating, which did little to prevent (or stop) rust in the B-post. So, I've got the same project ahead of me and plan to patch repair. Be sure to disassemble and really look for rust, to eliminate it throgoughly. It probably is deeper and more wide-spread than it might appear from the inside of the car, since that's where it finally burst through after some years damage is done, not where it starts.

What to do about the anchor plates is a hard question. It's a bit of a judgement call and would require hands-on inspection. If they are still quite sound, you might reuse them. If not, it's pretty simple to make up new from some thick, flat steel. It's a safety issue, so I'd err on the side of caution. Ideally, powder-coating would be a great finish for anchor plates (especially if you happen to have a batch of other parts going for powder coating). POR15 seems pretty good, too.

Back to the B-post.... I'd suggest after a coat of good primer is in place, or even after all the paint has been applied and the car is assembled, use lots of seam sealer from the outside to try to prevent any more intrusion from tire splash. Seam sealer can be bought in brushable form, or in "caulking" tubes to be used with a gun, or in cord-like rolls of putty material. Some is paintable, some is not. Get advice from your painter or paint supplier on what to use.
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[alphatopher]

Thank you guys for the tips. I think I'll put it back together as it was originally fabricated and apply a very liberal dose of seam sealer. After closer inspection my anchor plate is going to be my greatest headache. It has to come out, and I really didn't want to have to do this. I really HATE RUST!!!!