View Full Version : TR2/3/3A Tr3 Head Rebuild

12-16-2017, 04:37 PM
I am going to send the head to the machine shop. Replacing valves, guides, springs. Is it recommended to replace the collars and keepers as well?
Anything else I am missing?

12-16-2017, 04:57 PM
Split locks...yes.
Collars or retainers...only if you are changing spring types which are not compatible.

Also, check the valves for recession into the head. There is a good chance you will need new seats installed, and hardened exhaust seats are never a bad idea since they removed the lead from our gasoline.

12-16-2017, 06:35 PM
Have it crack checked and planed if not completely flat. You probably know that, but didn't mention it.

12-16-2017, 06:48 PM
You might consider using TR4A exhaust valves, and the special conversion guides. The thinner stem means less weight (which seems to help them last longer) and better breathing.

Personally, I've always reused the split locks and never had reason to regret that.

But I have had trouble with valve seat recession, so +1 on new exhaust seats.