I have any old mf 65 that when you engage the pto it works fine. When you try to disengage it will not disengage until you cut the tractor off. Any suggestion.
The service manual to make repairs to the clutch and such is located at www.agcopubs.com
There you will find a list of both tractors of many flavors and implements. There are CD's advertised on places like eBay but don't cover the many topics the factory service manual does. AGCO is the mother company that owns the rights to Massey Ferguson. There is a link floating around here on the site that mentions Dean Austins website that describes problems and fixes with clutches. At any rate unless you have a loose pedal bushing on the side of the tractor, it sounds like the clutch needs looked at. There is a clutch inspection plate on the bottom that will allow visual inspection for clutch movement. One can depress the clutch while the other with a flashlight can inspect it's movement. If the clutch is wore out and needs replacing, the tractor will need to be split in two to access it. It's not that big a deal if one knows what they are doing and have the correct setup for it. If not it was be a overwhelming task that should be left to a repair shop.
If you can engage the PTO with the engine running without any problems than the clutch should be fine. Are you trying to disengage the PTO by moving the lever without using the clutch and the PTO under load. I would think it would be very difficult and this would be normal. I always depress the clutch fully through its second stage when disengaging the PTO. The only PTO that could be disengaged easily under load would be a tractor with independent PTO, in this case the PTO engagement is operated by a hydraulic clutch and it appears that the 65 does not have it. When you shift gears forward or reverse, do the gears grind?