Massey Ferguson 85

[HaySeed 2]

Good evening, farmers I bought a Massey Ferguson 85 everything seemed to work, but the PTO will spin but doesn’t have any torque to turn the brush hog, but I still have power steering and I did find some flow valves on the right side down by the brakes and adjusted them completely in each direction with no luck. Any ideas I bought it out of sale so I think I got somebody else’s problem.

 

[da.bees]

The pto isn't hydraulic,it is gear driven. Look for a lever on side of transmission just in back of your left leg as you sit on seat. Up and rearward is engine pto you want for hog. Downward and foward is ground speed pto and midway between is out of gear, You must hold clutch all the way down to shift. If proper.ly adjusted , holding clutch half way down alows pto to continue running at full power while shifting gears. Try that and let us know if you have more questions. Not one of the most popular MF models from that era but a real workhorse non the less. Pick up an IT Manual at tractor supply for a wealth of repair and maintenance info.

 

[used red MN]

da.bees, do you have an MF 85? I don’t think the information you are giving is correct. That would be correct for a 65. The AGCO parts book shows two options per serial number breaks and both have a clutch pack that is applied by pressured fluid. AGCO MF 85 PTO parts diagram the right arrow in above the diagram should take you to the 2nd option.
Edit: Oops, been a while since I posted a link to the AGCO catalog. You will need to veiw sections 118 & 120.
Hello HaySeed 2, welcome to YT! Not sure if this is any help to i you. Sorry, but I guess I will point out the obvious, the clutch pack could be smoked.

 

[HaySeed 2]

Thanks for the info. I’ll check out those things tomorrow.

 

[miangus]

Used-red is correct the system uses a hydraulic clutch to provide an independent PTO function. It does share the hydraulic system with the power steering. Hopefully it's a control valve issue.

 

[Bob NY]

The pto isn't hydraulic,it is gear driven. Look for a lever on side of transmission just in back of your left leg as you sit on seat. Up and rearward is engine pto you want for hog. Downward and foward is ground speed pto and midway between is out of gear, You must hold clutch all the way down to shift. If proper.ly adjusted , holding clutch half way down alows pto to continue running at full power while shifting gears. Try that and let us know if you have more questions. Not one of the most popular MF models from that era but a real workhorse non the less. Pick up an IT Manual at tractor supply for a wealth of repair and maintenance info.

WRONG! The PTO on the 85 and Super 90 is engaged via a hydraulic clutch pack and the pressure is supplied by the power steering pump.

 

[da.bees]

Not mine but I pulled a baler on and off for 2 years with what I thought was a 85 but apparently I was mistaken. Maybe the clutch was what made them rare when there were so many other -5 and 1-5 models around in 60s and 70s.

 

[Bob NY]

The PTO clutch on the 85 and S-90 were unique in that they could be operated as either IPTO by simply moving the lever without using the tractor clutch or they could also be operated like a 2 stage clutch, depressing the pedal half way to stop ground travel and all the way to stop the PTO. Pushing the pedal all the way down dumped the pressure on the PTO cluch pack.

 

[miangus]

The PTO clutch on the 85 and S-90 were unique in that they could be operated as either IPTO by simply moving the lever without using the tractor clutch or they could also be operated like a 2 stage clutch, depressing the pedal half way to stop ground travel and all the way to stop the PTO. Pushing the pedal all the way down dumped the pressure on the PTO cluch pack.

You are correct. There is only a single stage clutch, the PTO is driven off a hub on the pressure plate. There is a dump valve in the transmission that dumps the hydraulic pressure in the IPTO system when the clutch pedal is fully depressed. Maybe the designers thought the more advanced system on the 85 needed to act like the system on tractors with the dual clutch. Or maybe it's a safety item, one pedal stops everything in an emergency. I believe there is also a valve that allocates pressure to the power steering.