MF135 stuck in 3rd gear!

   / MF135 stuck in 3rd gear! #1  

sglass01

New member
Joined
Aug 21, 2013
Messages
1
Location
Surrey
Tractor
MF 135
I topping my field yesterday when my 1969 MF135 got stuck in 3rd gear. I could change from high to low ratio and even stop and start the machine but the gear stick would not move forward.

I left it overnight to cool down and in the morning started it and after a couple of goes managed to shift it into neutral. All other gears seemed to work fine and (fluid levels are correct) so I tried 3rd again and it got stuck. After another cool-down period it freed and so I have parked it up and will not use 3rd for the time being.

Does anyone have a suggestion as to what the cause is and what repair is necessary.

Steve
 
   / MF135 stuck in 3rd gear! #2  
Since no one has jumped in yet I will offer some comments derived from another brand of tractor which may give you some insight.
If the top of the gearbox can be removed consider doing this. Inside you will find the selector forks which move the gears. The forks are on rails running the length of the gearbox.
Where the bottom of the gear shift lever meets the rails (there will probably be 3) each rail will have a socket or hole that the gear shift lever fits into to be able to slide the rails and in doing so move the forks.
Each rail socket will be at the same place when the transmission is in neutral. As you move the gear shift from side to side the bottom of the lever will engage different rail sockets.
The rail sockets have their movements co-ordinated by ball bearings and springs which lock all rails except the one you have selected. As parts wear the co-ordination parts wear or break allowing the selector rails to move when they should not. A dragging clutch which keeps pressure on the gears can make these unwanted selector rails move. Because the rail moved without the bottom of the gear shift moving it, the gear shift is blocked from accessing the rail and you are stuck in gear. Another possibility when the co-ordination parts wear is that the transmission gets in 2 gears at the same time and is effectively locked.
Dont be afraid to go at it. Have a camera to record the position of parts as you go.
Dave M7040
 
   / MF135 stuck in 3rd gear! #3  
Sorry for your problems.

A 1969 model, assuming it has been well worked, is probably getting a bit worn in the gearbox department. There are only two possibilities, external and internal. If the linkage is all proper, clutch good, your problem is internal to the transmission, bearings, gears, forks, etc. I think you are going to need to open her up.
 
   / MF135 stuck in 3rd gear! #4  
Repost this in the Massey Ferguson Vintage forum so the resident Guru's can find it. Welcome to TBN.
 
   / MF135 stuck in 3rd gear! #5  
Repost this in the Massey Ferguson Vintage forum so the resident Guru's can find it. Welcome to TBN.

Sound advice! There are a couple of threads there on MF stuck in gear topics along with a screwdriver fix, if that is your problem.

Dave, for some reason I overlooked your post. Also good information and jives with what I saw in the MF threads.
 
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   / MF135 stuck in 3rd gear! #6  
Our MF135 is 4 spd... have had issue with it getting stuck in 2-4 which are to the right side with 3rd in the middle and R and 1st on the left. Rather sure our issue is a worn shifter where it engages the shift rails as it pops out of the rail allowing the shifter into the neutral position but the 2-4 rail is still partially in gear.

Your problem sounds very different... sounds like your shifter isn't flopping around like it's in neutral but fixed and clearly in the gear position but it just won't move. Sounds like something on the shift rail binding up.
 
 
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