Newbie Question: Can't disengage the PTO with the mower still spinning

[AxleHub]

So I am certainly a tractor newbie (especially when it comes to larger tractors greater than 25 HP).

I was test driving a Massey 261 (60 HP, 53 HP PTO) yesterday from a private seller and everything seemed fine. A 7 foot 3pt rotary mower is included with the sale.

The only thing that surprised me or more importantly made me reluctant to purchase was the fact that with the clutch fully engaged the PTO would not disengage until the rotary mower stopped spinning. Since the mower stopped spinning I assume everything is OK with the PTO Clutch or brake or whatever BUT is this normal?

Should I be able to disengage the PTO as soon as the clutch is fully pressed without waiting for the mower to spin down?

This might be a silly question but I have never purchased a tractor before and never really used anything bigger than a 4 ft rotary. I appreciate any help or additional info.

Just wondering . . . it seems like this is a huge change in equipment sizing for you. Is there enough motivation to jump such a gap in equipment sizing . . . that will allow you to be comfortable?

 

[Texasmark]

Back in the day of the tranny driven PTO, without an overrun clutch installed between the tractor PTO shaft and the implement, the problem was common. With the advent of the "Live" PTO you had a dual clutch where you could disengage the implement before you disengaged the engine from the tranny and had no problem. Then comes the Independent PTO which is independent of the tractor drive function and you can engage or disengage at the flip of a switch for electrically controlled or with a lever for manual. Some Independents, like mine for example, have a PTO brake that stops the PTO from turning when you turn off the PTO.

I don't know what your Mahindra uses. Find out and check what I said above. If you have Live and have the problem, I'd say your clutch linkage isn't properly adjusted.....on older Fords with Live, depressing the clutch pedal approximately half way disengages the PTO clutch and the implement will quit turning when the resistance overcomes the existing inertia of the blade turning when you disengage. There is no brake on the PTO shaft. As you push the pedal farther down, you disengage the axle drive and the tractor comes to a stop on flat ground.

 

[flusher]

With my 2005 Kubota B7510HST (21 hp engine) and my 2008 Mahindra 5525 (55 hp engine), both with two stage clutch and an internal overrunning clutch, I just pressed the clutch to disengage the pto and shifted the pto lever from ON to OFF with the brush hog spinning. Never had a problem with either tractor. I kept the brush hog raised about 6 inches above ground while it spun down so I could climb off the tractor without risk of the mower throwing something in my direction.

The internal overrunning clutch (aka sprag clutch) in all modern tractors connects the engine to the mower only when the engine is providing torque to the pto drive shaft to spin the mower. When you press the clutch, the engine torque is removed, the overrunning clutch disconnects, and allows the mower and the part of the pto drive system between the ORC and the mower to free-spin down to zero rpm.

Some implements like my Massey Ferguson 124 baler have an additional external ORC that's part of the baler flywheel assembly. Helps protect both the tractor pto driveline and the baler while the baler flywheel is spinning down. Brush hogs and balers also have slip clutches in the pto driveline to protect the tractor and the implement in case something jams up the implement rotary mechanism. Older implements sometimes had shear pins for this purpose.

Good luck with your tractor purchase adventure.

Welcome to TBN. Join the fun. And be careful out there whilst enjoying your tractor experience.

 

[geneP]

I think you should post this on the Massey Ferguson forum on this site. I THINK (emphasis on think) some tractors have a PTO selection for "transmission" driven PTO and "live" PTO. As stated above a transmission driven PTO will not shift or stop while the mass is moving and there is no slip clutch installed on the PTO shaft. Ask about another position on the PTO selector to place it in the "live" position.