Popping out of 3rd gear

[jdoclogan]

I have a friend who put in a newly built all-synchro transmission/OD. It keeps popping out of 3rd gear while running in normal operating mode. Any ideas?

 

[DanR]

Doc, Is normal mode both In and out of OD ?

 

[jdoclogan]

Just as Kris is driving along out of OD.

 

[DanR]

I would think a sync ring could be bad.

Are there any vibrations?

Assuming it does not malfunction while in 3rd with OD engaged?

 

[alpine_64]

Is it popping out when lifting off after acceleration or as he accelerates? These are signs of the synchro being worn...

If it was popping out while at steady throttle and cruising.. Maybe the selector fork or detent springs arent set right....but that would also impact the gear change into that gear

 

[Tim R]

On my car I've noticed that when I accelerate in 3rd and go to change up it is very eager to disengage from 3rd, almost like is part disengaged already. It hasn't popped out (yet) but I'm thinking that something is worn and that sooner or later it is going to.

Tim R

 

[beamdream]

Struggling to see how OD would have any influence on this. All the OD activity takes place behind the gearbox internals.

 

[Scotty]

What oil is in the Trans and OD?

 

[RootesRooter]

If its popping out while off-throttle, its a worn 3rd/4th gear shift fork.

 

[Mike O'D]

Pretty certain it's the spring loaded ball detent on the shift rod. It's addressed in the workshop manual. I don't have it handy to give you the exact section, but shouldn't be hard to find. Had the same situation with mine -made the adjustment and solved the problem.