‘58 B-61 Duplex 1st gear hanging

[pdgx]

I have a ‘58 B-61 with a duplex transmission that wants to hang up in 1st gear.

I suspect it’s a worn detent/ball. 

Does anyone have a parts manual with an exploded view showing the 1st detent area ? 

Would appreciate a pic of the page(s). 

Thx

[mowerman]

You might just have dried out fork slide bar  I’m sure you’ll get all kinds of reply’s good luck

[Freightrain]

This is all the old Mack manuals show.

No other details, just specs for bearings and such.

I rebuilt my Triplex using similar picture and the instructions in the book.  I made three videos showing the process.

I didn't mess with the covers as they were not an issue.

 

[pdgx]

Thanks for that. Watched the video. 
What could be holding the first from disengaging 1st ? Didn’t see anything in the disassembly that would point to it resisting. 
When it does stick, it takes a couple of loaded clutch activations to let it release. 
Of course it always gets you when pulling into an intersection……

[Freightrain]

Good question.  It doesn't do it every time?  Only under a "heavy" load of acceleration or even if you just take off easy?

Could be a detent ball on the shift rail or maybe the sliding clutch on the main shaft.

[Mark T]

Sliding clutch, or moving the gear with it a little.  Not an easy quick fix for that sort of thing.

[mowerman]

I was thinking maybe clutch not disengaging all the way 

[Freightrain]

4 hours ago, Mark T said:

Sliding clutch, or moving the gear with it a little.  Not an easy quick fix for that sort of thing.

Oh ya, that is an entire tear down deal.

Have you had the lid off?

[pdgx]

I wish I could say it’s consistent, but it’s not.  It just gets you when you don’t expect/want it. 
On level or a down grade start, it will ‘usually’ stick..(except on the second Tuesday of the week). Aux low or high makes no difference..

If I put the aux trans in neutral first, it will release. But then you can get stuck in double neutral on the way to 2L. (1H to Aux L will not let you out of 1 to get to 2L)

On a slight UPHILL start, it will usually release.  ??

At very low speed <5mph, it will release.

Repeated attempts to replicate with F/R, will ‘usually’ allow it to release in subsequent starts - hi or low. (Yes the trans oil is at full level, and you can travel long distance and still hang w next start, so lube should not be a problem)

Makes no difference bobtail, or loaded towing. (Obviously don’t need 1st when bobtail, but it still sticks w no load)

Just a PITA when towing loaded. 

[pdgx]

3 hours ago, Freightrain said:

Oh ya, that is an entire tear down deal.

Have you had the lid off?

No. Have not pulled or opened it as it’s my only tractor at the moment.