Transmission problem

54FergieTO30 · Oct 1, 2017

Found a great running and great looking 1963 MF35 Deluxe with multi power. Got it at what I felt was a good price, the reason it was a good price is it's stuck in gear. I have read a bunch of posts on here about fixing it, but did not have any luck working through the filler hole.
So steering/trans cover is off.
HiLo selector moves freely and is in the start position
Clutch is clamped down.
Gears can be turned.
Both shift rails are stuck and will not move when pried on with a crow bar.

I don't want to bend or break anything, so hopefully someone out there can educate me on the fix for this.
.

Dieseltech · Oct 1, 2017

All three rails should move easily with the shift cover off, and no tension on the three hold down springs. Will the three springs and each rail detent lift out with a magnet? They should come out easily. Then either the rails are rusted/stuck in place, and/or the interlock pin could be stuck at the rear of the rails too. Need to split the it at the trans/diff joint to see the interlock though. Make both R/1 and 2/3 shift forks are not broken too. Had that happen before years ago on a MF 50 at the dealer I worked for..

54FergieTO30 · Oct 1, 2017

(quoted from post at 17:44:43 10/01/17) All three rails should move easily with the shift cover off, and no tension on the three hold down springs. Will the three springs and each rail detent lift out with a magnet? They should come out easily. Then either the rails are rusted/stuck in place, and/or the interlock pin could be stuck at the rear of the rails too. Need to split the it at the trans/diff joint to see the interlock though. Make both R/1 and 2/3 shift forks are not broken too. Had that happen before years ago on a MF 50 at the dealer I worked for..

Springs came out easily, rail detent did not come out with magnet. I just put some penetrating oil in each hole, we will see if that helps.

Dieseltech · Oct 1, 2017

That MAY be where the trouble is. The detent pins must raise when the rails move, soak them well and apply more force to each shift rail to get them moving. do one rail at a time, returning it to neutral before moving the other rail. The rear interlock will allow only one rail to move at a time. The detent pins MAY need tapped down too so the lube can work around them. Just make sure the rail is in neutral, or either forward or reverse so the rail groove is in line with the detent pin.

54FergieTO30 · Oct 1, 2017

Got the detent pins out. Looking through the hole it appears the rails are on the middle notch, which I think should be neutral. However I still can't get them to move.

Dieseltech · Oct 1, 2017

Pry harder...

clarence julian · Oct 2, 2017

I had the same thing happen to me years ago. my detent pins were rounded off from wear I bought 3 new ones. they caught the groves and wouldn't move, they don't get any lube up there I think.

DavidP, South Wales · Oct 2, 2017

Hi, to add a little to DT.....you have mentioned that the rails appear to be 'seized'. Are they actually solid in the gearbox casing or is there a little movement but not enough to slide at all? The appearance of the gearbox would appear to rule out rust as a cause which really only leaves the interlock at the rear of the gearbox. A very badly worn pin here could possibly allow the attempted engagement of two gears at once. With the selector slots in line which suggests 'neutral' and one rear wheel jacked clear of the ground can you turn the flywheel without turning the rear wheel? If you are able to turn the engine/flywheel by hand without turning the wheel then that suggests that you are in neutral. If the wheel turns I would suggest moving/tapping both selectors forward or rearward to release the interlock pin if it is jammed and find the correct neutral position for both selectors. Let us know how you get on.
DavidP, South Wales

54FergieTO30 · Oct 2, 2017

(quoted from post at 03:42:30 10/02/17) Hi, to add a little to DT.....you have mentioned that the rails appear to be 'seized'. Are they actually solid in the gearbox casing or is there a little movement but not enough to slide at all? The appearance of the gearbox would appear to rule out rust as a cause which really only leaves the interlock at the rear of the gearbox. A very badly worn pin here could possibly allow the attempted engagement of two gears at once. With the selector slots in line which suggests 'neutral' and one rear wheel jacked clear of the ground can you turn the flywheel without turning the rear wheel? If you are able to turn the engine/flywheel by hand without turning the wheel then that suggests that you are in neutral. If the wheel turns I would suggest moving/tapping both selectors forward or rearward to release the interlock pin if it is jammed and find the correct neutral position for both selectors. Let us know how you get on.
DavidP, South Wales

I believe it is in neutral. Turning motor over with one wheel jacked up does not cause wheel to turn. The shift rails will move ever so slightly so they are not frozen in place. Is there something in the rear that would be causing this that I need to split the tractor to see?
I can turn ever gear in there so it does not seem to be stuck in gear. I have read all these posts that say to just pry, believe me I have tried. 3 foot crow bar...no luck on moving either rail.

54FergieTO30 · Oct 3, 2017

(quoted from post at 17:44:43 10/01/17) All three rails should move easily with the shift cover off, and no tension on the three hold down springs. Will the three springs and each rail detent lift out with a magnet? They should come out easily. Then either the rails are rusted/stuck in place, and/or the interlock pin could be stuck at the rear of the rails too. Need to split the it at the trans/diff joint to see the interlock though. Make both R/1 and 2/3 shift forks are not broken too. Had that happen before years ago on a MF 50 at the dealer I worked for..

The detent pins have been removed. The rails can be ever so slightly moved, so they are not rusted in place. Does the parts manual show this "interlock"? I don't have that manual. I don't know how the interlock works, but could it be my problem?

Dieseltech · Oct 3, 2017

The rail interlock pin is at the rear of the transmission, it slides back and forth in the holder to allow only one rail to move. Never had trouble with one, but it could be stuck. Need to split at the trans/diff case joint to get at it. MP pump oil line will need disconnected also for the split.

54FergieTO30 · Oct 5, 2017

(quoted from post at 08:42:48 10/03/17) The rail interlock pin is at the rear of the transmission, it slides back and forth in the holder to allow only one rail to move. Never had trouble with one, but it could be stuck. Need to split at the trans/diff case joint to get at it. MP pump oil line will need disconnected also for the split.

Split the tractor tonight. Removed rail stop to see if it was binding ...it's not. I also hammered on the end of each rail, no movement. It seems like the gears are stuck on the main shaft and won't slide. I can't seem to post a video on here. But I did on the FENA Facebook page.

54FergieTO30 · Oct 8, 2017

(quoted from post at 18:35:38 10/05/17)

(quoted from post at 08:42:48 10/03/17) The rail interlock pin is at the rear of the transmission, it slides back and forth in the holder to allow only one rail to move. Never had trouble with one, but it could be stuck. Need to split at the trans/diff case joint to get at it. MP pump oil line will need disconnected also for the split.

Click to expand...

Split the tractor tonight. Removed rail stop to see if it was binding ...it's not. I also hammered on the end of each rail, no movement. It seems like the gears are stuck on the main shaft and won't slide. I can't seem to post a video on here. But I did on the FENA Facebook page.

Shift rails are out and are not the problem. Both gears are seized on the main shaft. Both shift forks are discolored on the tips like they have been really hot. Is this an indication of my problem?

54FergieTO30 · Oct 9, 2017

(quoted from post at 19:47:43 10/08/17)

(quoted from post at 18:35:38 10/05/17)

(quoted from post at 08:42:48 10/03/17) The rail interlock pin is at the rear of the transmission, it slides back and forth in the holder to allow only one rail to move. Never had trouble with one, but it could be stuck. Need to split at the trans/diff case joint to get at it. MP pump oil line will need disconnected also for the split.

Click to expand...

Split the tractor tonight. Removed rail stop to see if it was binding ...it's not. I also hammered on the end of each rail, no movement. It seems like the gears are stuck on the main shaft and won't slide. I can't seem to post a video on here. But I did on the FENA Facebook page.

Click to expand...

Shift rails are out and are not the problem. Both gears are seized on the main shaft. Both shift forks are discolored on the tips like they have been really hot. Is this an indication of my problem?

Small victory. Drove a wedge between the two gears and one broke loose. The other is still stuck. The one that is free will get stuck again if I move it back to the neutral position.
Could the splines be slightly twisted causing these gears to bind?

ptfarmer · Oct 9, 2017

All the things that stuck together, or if the teeth on gears, and splines don't look smooth I'd replace them.

54FergieTO30 · Oct 15, 2017

(quoted from post at 19:05:12 10/09/17) All the things that stuck together, or if the teeth on gears, and splines don't look smooth I'd replace them.

Well I have the main shaft out and the gears removed from the shaft. Had to cut the shaft to remove it because the gears would not slide on the shaft. Now that it is out and on the workbench it is easy to see the problem. The shaft has to have a slight twist in the splines because the gears slide for a bit then hit a place on the shaft where they bind. There was no way to "unstick" this problem. If I was able to do so it would have stuck again the next time it was shifted. Trying to locate a used shaft now. A new one from YT is about $120. It was a good day, problem figured out, now just need parts and reassemble.

54FergieTO30 · Oct 27, 2017

(quoted from post at 19:35:20 10/15/17)

(quoted from post at 19:05:12 10/09/17) All the things that stuck together, or if the teeth on gears, and splines don't look smooth I'd replace them.

Click to expand...

Well I have the main shaft out and the gears removed from the shaft. Had to cut the shaft to remove it because the gears would not slide on the shaft. Now that it is out and on the workbench it is easy to see the problem. The shaft has to have a slight twist in the splines because the gears slide for a bit then hit a place on the shaft where they bind. There was no way to "unstick" this problem. If I was able to do so it would have stuck again the next time it was shifted. Trying to locate a used shaft now. A new one from YT is about $120. It was a good day, problem figured out, now just need parts and reassemble.

Found a used shaft. Put new bearings in and used the old gears. The gears now slide as they should along the shaft. So the old shaft was definitely the problem. I am guessing the previous owner ran it low on oil and got things hot to cause this problem. Hope to get it all reassembled this weekend and give it a test run.

Transmission problem

54FergieTO30

Member

Dieseltech

Well-known Member

54FergieTO30

Member

Dieseltech

Well-known Member

54FergieTO30

Member

Dieseltech

Well-known Member

clarence julian

Member

DavidP, South Wales

Well-known Member

54FergieTO30

Member

54FergieTO30

Member

Dieseltech

Well-known Member

54FergieTO30

Member

54FergieTO30

Member

54FergieTO30

Member

ptfarmer

Well-known Member

54FergieTO30

Member

54FergieTO30

Member

Similar threads