Farmall M MW Hand Clutch

If it's just slipping (tractor will not drive at all) you can try increasing the pressure on the clutch assy by tightening the large nut under the side plate on the clutch. Book says should require 25-40lbs of pressure to move the handle. If you have pleanty of pressure, you might have all the teeth stripped off the fibre discs which will need to be replaced. There will be either 3 or 4 in your setup (Super M or straight M) but good luck finding them. I've heard rumors of them being offered various places, but no solid leads so far. We had to make a set several years ago probably would have cost less to pull the clutch and put all the original parts back from a salvage yard.
Stan(VA).

The metal disks are spaced between the fiber disks. When they are compresed together. You get motion. When the presure is released. The outer and inner disks move independent of each other and motion of the trator is stopped. Wile the PTO still spins.
The compresion of the disks is acomplished via a ramp and roller set. When the handle is moved this forces the ramp to ingage the rollers. Pushing them into the plate that pushes the clutch disks Causing ingagement.

Wear of the disks is what causes the clutch to slip. Once the wear is past the ability of the ramp and roller to ingage the clutch. Well you dont move.

If disks are not warn out you can adjust the ramp and roller to compensate for the wear.
Remove the cover on the front of the clutch and there is a big nut that you can tighten to take up the slack. If this does not work then the fiber disks need replacing. If you need to replace the disks. Good luck finding a set. M&W does not support them any longer. There are some companys that specialize in geared facings. But its not a easy task to get them to help you as they like big customers. But it can be done.
Good luck.

• M&W Clutch