TR4/4A The 4A gearbox anti rattle contraption?

[karls59tr]

I have one on my parts shelf. It's a large cast iron ball with a bracket which I believe was supplied by Triumph to 4 or 4A? owners who complained about a buzzing noise in 3rd? gear due to vibration. Do I have the story straight?

 

[Rod-H]

Wow, I've never seen that. That is so Triumph-Standard.
"We have Band-aides in all shapes and sizes".

Rod

 

[Andy Blackley]

Yes, its a vibration damper. Here is some info, courtesy of the TR Register forums.

 

[RJCOX]

I've got one of those sitting in my parts washer.

Pulled it from the TR4 transmission that I installed in my 3. Knew what it was, but the 3 never had it, do yanked it.

 

[Andy Blackley]

Some say it was only needed when ST increased the bore size to 86mm on the TR4. The bigger engine supposedly produced some added vibration in the 2700-3000 rpm range. Could be related to the fact that the intermediate exhaust pipe hanger was bolted to the back of the gearbox to utilize the rubber TR4 rear gearbox mount, whereas the earlier cars bolted the hanger/clamp to chassis.

 

[sp53]

That is amazing. I love it.