Farmall 200 PTO

Farmall 200 power take-off runs continuously regardless of the position of the control lever.
How do I stop it?

Remove it from the tractor & inspect the shift lever & related parts.
You will need 1 gasket.

I suspect that the brass pilot bushing in the end of the transmission shaft that powers the PTO is hanging on the PTO shaft. You will need to remove the PTO and replace that bushing along with any bearings that may be bad.

First check by placing the PTO in the disengaged position with the tractor off and attempting to turn the PTO shaft with your hand. If you can the following does not apply and you have other issues. If you can turn the shaft under those circumstances then put the PTO in the engaged position and attempt to turn. You should not be able to turn the shaft with your hand in the engaged position. If you can't turn the shaft in either position then the following applies. The PTO drive shaft that runs from the front of the transmission to the rear of the tractor is accessible behind the belt pulley assembly or the belt pulley delete plate. You do not need to remove the actual PTO shaft which is driven by a gear on the before mentioned shaft to fix this issue. This shaft has a splined slip shield that engages a splined mating hole in a shaft at the front of the transmission that turns anytime the clutch is engaged. The slip shield is slid in and out by the control lever. It is possible to assemble the shaft and slip shield and fail to properly mesh the control lever so that it can engage or disengage the shield with the shaft at the front of the transmission. This would likely happen if the top were taken off the transmission for any reason or if the shaft had been pulled recently. When you remove the belt pulley or pulley delete plate, you can remove the shaft by removing the bolts encircling the shaft. The slip shield should be engaged when you remove the shaft. If it becomes disengaged you will have a difficult time reassembling the shaft shield assembly. You have to remove the shaft to examine the location of the control fork. Here it gets fuzzy since I believe you can re-engage the control lever through the hole after removing the shaft. The gasket you may need will be between the belt pulley assembly and the transmission frame. I do not think they are available from CIH so you will have to make a gasket from stock if you need one.
If the test done at the beginning showed that the shaft was disengaging then you could have too much oil in the rear end or the entire assembly needs cleaning. You will most likely have to remove the top of the transmission to clean the shaft assembly but you can try by cleaning the shaft when you have it out to examine the control lever location. If the tractor was stored outside for a length of time there will be rain water in the rear end. You can check for that by removing the drain plug to see if the first liquid out is oil or water. If water there are historical post on this forum on how to remove the water, clean the transmission box, and replace the oil.

Is it turning at full speed or just slowly?

David