‘58 B-61 Duplex 1st gear hanging

[Geoff Weeks]

Well if it goes into 2nd fine at a stop, that pretty much rules out clutch issues. Remember we can only comment based on what you tell us, only your eyes and fingers on the truck. Could be interlock issue in the shift tower.

[pdgx]

There is no problem getting into any gear. 
 

Only getting out of 1st when it decides to stick..

Edited 25 minutes ago by pdgx

[Freightrain]

Thinking more about detents and interlocks.  That sounds more a viable issue since it works fine without engine running.  No vibration or gears turning and pulling on the shift forks.

I would have to really think back to what all is going on with the shift rails when in a gear.

This is only picture I have handy of lid.  Not sure if I have anything better.

I may have something on my home computer that I backed everything up on.  It may give some insight on what happens when it is put in a gear and what may be holding it.

[pdgx]

10 minutes ago, Freightrain said:

Thinking more about detents and interlocks.  That sounds more a viable issue since it works fine without engine running.  No vibration or gears turning and pulling on the shift forks.

I would have to really think back to what all is going on with the shift rails when in a gear.

This is only picture I have handy of lid.  Not sure if I have anything better.

I may have something on my home computer that I backed everything up on.  It may give some insight on what happens when it is put in a gear and what may be holding it.

Again, thanks for the pic.  I turned the lights on to see it better…..
 

Don’t know if that’s the 1st gear fork, but is there a detent ball in that location circled ?  Does the rod slide in/out, or just the fork move on the rod ?

I’m not familiar with this transmission internals, but that is what I’ve been thinking as a possibility. ???
 

If so, is there an exploded view of that boss and a detent ball ?

Can the ball be deformed or flat spotted ? Just wondering. 

And what position is the fork and rod in, when in gear vs out on 1st ?

[Joey Mack]

1st gear is at the rear of the main box, in front of reverse. 1st and rev. share the same fork and sliding clutch. the small fork should be 4th/5th..

[pdgx]

17 minutes ago, Joey Mack said:

1st gear is at the rear of the main box, in front of reverse. 1st and rev. share the same fork and sliding clutch. the small fork should be 4th/5th..

So the 1st gear fork is on the right side of his pic ?

Didnt know what way he had the cover laying for the pic. 
 

The fork/rod would operate the same