Farmall 140 Transmission NEED HELP

It seems like 3rd and 4th gear are going in at the same time on the Farmall 140 tractor. You can take the shifter top off and put it in neutral manually and when you replace the top something happens and it goes back in gear. We just got the tractor and it wasn't running and the owner had just passed.

I'm not sure if those are the gears that are going in, but it looks like it.

What do you think is going on and how can I fix it? I tried a different shifter and top and it didn't help.

3 and 4 are on the same shift fork, so having it go into both at once is not possible.
There are detent balls and springs that keep a shift rail and fork positioned. If the springs are rusted/missing/broken, or balls missing rusted, it can allow rails to move where they should not, allowing the trans to be in 2 gears at once.
The balls/springs are in the cover, I would make sure they are operating as designed (easy as the trans can stay intact)
Make sure all three forks are correctly on their respective gears upon assembly. Jim

My 100 will lock up like that particularly if I put the transmission in a bind. I learned to not do that.

Mr Janicholson - isn"t there also a repair of rebuilding the tip of the shift lever in a specific pattern that helps correct this ?

IIRC the tip of that shifter is a ball shape. If it is distorted, making it as new would be a good idea. We still do not know what the issue is due to the lack of facts. Jim

Ok, when you take the shifter off this time, make note of which forks are in which positions.

Do the forks slide smoothly, or pop from position to position? Smooth is bad. Means the detent balls have fallen out. Transmission has to come apart.

If the forks pop from position to position, then you're not getting the ball on the end of the shift lever aligned with the slot in the shift forks.

(quoted from post at 17:28:07 05/16/14) Ok, when you take the shifter off this time, make note of which forks are in which positions.

Do the forks slide smoothly, or pop from position to position? Smooth is bad. Means the detent balls have fallen out. Transmission has to come apart.

If the forks pop from position to position, then you're not getting the ball on the end of the shift lever aligned with the slot in the shift forks.

Click to expand...

Why would the transmission have to come apart if I am checking to see if the shifter top and forks operate smoothly or not? Aren't the detent balls in the shifter top?

RTR, no need to pull the cover to check the detent balls - if the shifter 'snaps' and holds into each position, the springs and balls are ok.

I may be wrong here, but I believe the 140 tranny is no different than the SA, and I fixed my SA last year from doing much the same thing.

The bottom of the shifter rod should be a "rectangle" shape blade, about 5/16" thick, and about 5/8" front to back, with a slight rounding to allow for the arc of the throw (front to back) within the shift fork.

side view (spacedots.) front view
..|......|. . . . . . . . . . . . \. . ./
. \___/ <-- rod -------> \. ./
. .(__) <-- shift blade -> |_|

I think someone here posted photos of the repair they did. A search may find it.

Mine was worn more like a wedge because the pivot pins were shot. It would slip between the forks leaving it in 2nd or Rev, and put it into 3rd or 1st (respectively) as well. I pulled the shift rod from the cover, checked springs and balls, added weld (6011) to the sides of the shift blade, then ground it back to proper shape; replaced the pivot pins (IIRC, about $20 from CNH), and it's back to near original.

It sounds like yours may have a bad detent spring, or when put together, one of the shift forks isn't in the slot in it's sliding gear. I had to try 3 times to get the forks in the gears because it doesn't take but a nudge to get them to move down hill (my dirt floor equipment shed isn't level). It would probably help to have it parked on dead level ground for such work.

Let us know what you figure out.

yeah, I'm sorry but it is hard to follow your diagram and description about what might be wrong without some actual pictures.

Maybe this evening or tomorrow morning I can get some pictures of what is going on with ours

when we got the tractor we had to take the top/shifter off to get it out of gear. Once at home we were going to replace that top/shifter with another one from a parts tractor, but upon installing it, when in Neutral the tractor is still in gear! haha

Sorry, got my mental parts books crossed up a bit...

I forgot the detent balls are in the cover on the 140.

So yeah, you've got to be dead-nuts on or else you'll shove a shift fork out of position when you're re-installing the shifter, and you'll be right in the same boat as before.

He's talking about the tip of the shift lever that pokes into the transmission. They get worn after 50 years or so.

It should be a nice slide fit into the shift rails and wide enough that it can't slip or wedge between two rails and cause the problem you're having. It's 100% certain that the tip of your shift lever is worn down, rounded off, etc.

(quoted from post at 23:45:47 05/16/14) Sorry, got my mental parts books crossed up a bit...

I forgot the detent balls are in the cover on the 140.

So yeah, you've got to be dead-nuts on or else you'll shove a shift fork out of position when you're re-installing the shifter, and you'll be right in the same boat as before.

He's talking about the tip of the shift lever that pokes into the transmission. They get worn after 50 years or so.

It should be a nice slide fit into the shift rails and wide enough that it can't slip or wedge between two rails and cause the problem you're having. It's 100% certain that the tip of your shift lever is worn down, rounded off, etc.

Click to expand...

I'm taking this as the opposite tip of the shift rod that you grab.....which is the part that touches the shift forks. ?