Alfa Romeo Forum banner

Studs shearing on new alloy carb mounts (1972 S2 Spider)

1075 Views 12 Replies 6 Participants Last post by  GTA R
We have had a problem with a stud shearing on a new set of alloy Carb mounts that were fitted to my son's S2 Spider. These Carb mounts were supplied about 9 months ago by a very well known supplier of Alfa Romeo parts in the UK, whose name I won't mention right now.
The stud failed sometime within the last 6 months, after the carb mounts were fitted by a reputable and highly experienced Alfa Romeo specialist, back in May this year. This subsequently gave rise to some engine idling problems, seemingly where the carb mount was not sealing properly against the inlet manifold.
We've recently discovered that someone else had exactly the same kind of problem with studs shearing on new alloy carb mounts. Indeed his problem was even worse, as he had 5 of them shear on his Spider. His sorry tale is written up on the other Alfa forum, for anyone who's interested.
I'm keen to know if anyone on this forum has experienced similar problems, as the supplier doesn't appear to want to acknowledge that there is a manufacturing fault with these components.
I'll post up a couple of photos to illustrate the problem in a later thread.
Thank you,
1 - 4 of 13 Posts
Yes, that is the other thread I was referring to and here are a couple of photos to illustrate what we found when we took off the manifold and carb mounts.


See less See more
I'm surprised at the suppliers reaction, I use them for all my bits and pieces and any problems are quickly and easily resolved
It very much depends upon who you get on the phone. The guy who my son spoke to claimed he had never heard of this problem and made my son pay for a new stud (as if it was our fault the damn thing had failed) so I'm afraid we're not very impressed. I'm planning to take this up with them on Monday.
What are you using to fasten the carbs on to the mounts? I think (but don't know for definite) that these kind of mounts should use MISAB cups and rubbers. You must make sure there is a 2mm gap between the cups. i.e. don't tighten them up so the cups are touching.

Do you still use the carb steady which comes up from the engine mount with these mounts?
Yes, thanks for that information. However it's Delorto carbs that are fitted, so I don't think the rubber and washer kit you mentioned is suitable. Unfortunately the carb stay bracket was removed when the old Solex carbs were removed and replaced by a mechanic several years ago and we haven't been able to source a replacement one, suitable for the Delortos. However someone at CA told us that we didn't need the bracket anyway, if we were replacing the rubber mounts with the alloy ones they supply.
1 - 4 of 13 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.