Sombrero Mounts

[Chris L.]

Well,
I've heard of this happening before, but now it's happened to me. I purchased a pretty original 67' coupe that the previous owner used to Solom Race back in the day. (He owned the car since 1969) When driving home from my local CnC the rear started making funny noises and felt odd while turning. After looking at the rear suspension and not finding anything loose, I was stumped. So being confused and just looking at everything I could think of, I noticed that the left rear Sombrero mount that is welded to the frame has broken loose! Upon further inspection, I could see that it had been poorly welded on in the past. (Not a factory type weld anyway) I'm guessing this is not the first time it has happened. Anyway, my question is can this be welded "correctly" with the body on the frame or do I have a lot of work in front of me? I can see that I'm going to have to remove most everything, from the center crossmember back, to get the desired access for the repair anyway. What does the conscious have to say? Sorry for my long-winded post.
Regards,
Chris

[Chris L.]

[Richard M.]

Re: Sombrero Mounts

Chris, Is this a big block car? The higher torque engines typically overstress those mount gussets. If SB, those Slaloms probably contributed to the fault.

With body on it would be quite difficult, but possible. It depends entirely on access to all welds and to be able to accurately place the new piece and access to the top of the gusset to properly weld the round sombrero to the mount gusset. The gusset mount itself needs to be welded to the crossmember at its top horizontal. It's really tight up there.

If I were to attempt it with body on, I'd remove...

Gas tank
Rear spring
Rear sway bar (if BB)
Differential assembly attached to removable crossmember(i.e. at the 2 sombrero mounts)
Both L & R Trailing arms

So, to give you a better idea of the details of replacing one with body off, see these posts from a 1967 build from several years ago. You'll also see there were some other areas of the frame that needed to be fixed in the gusset mount also.

After media blast showing failed gusset details. It was repaired with body on years prior, poorly done as it was brazed...
Here

Repair process...
Here

Repair piece details...
Here

Try to get some photos up and under your failed gusset if possible.

Rich

[Chris L.]

[Stewart L.]