Rotary cutter / mower / clipper / bushhog -- blades stopped spinning

[livemusic]

I have a Woods Heritage HC72C rotary cutter on a Mahindra 5010 tractor that I bought used a year ago. I think it's maybe 2014 or thereabouts models. The mower blades suddenly stopped turning clipping a pasture after I had been mowing a couple hours. It appears to me that this cutter has a slip clutch. I have no idea where to start with a diagnosis. I hit a few large fire ant mounds and also a firewood round (large oak round), I could not see these in the tall grass. But I kept mowing with no issue for a long time, probably an hour, after these 'hits.' The mower shuttered but it seemed fine.

I took the shaft off the PTO and the PTO spins fine. So, how do I diagnose what is going on and fix it? I first thought it might be a shear bolt but I see what appears to be a slip clutch atop the mower near the gearbox. Which I know not much about other than a youtube! Which I rely on but I can't find any info on this problem with the mower just suddenly free-spinning and not cutting. I am not exactly a mechanic expert!

I need to check oil in this gearbox as well. Maybe I can find a Woods manual. Thanks for any help.

 

[ericm979]

Detach the PTO shaft from the tractor and block the mower blades in place, then try turning the shaft by hand to see if the clutch slips. It'd have to be really wasted to turn under hand pressure.

If it doesn't, the slip clutch may be slipping under light load. To check that, remove the PTO shaft from the mower. Remove the guard bolted to the gearbox so you can observe the slip clutch. Mark the clutch and the plate(s) with a paint pen or similar. Then re-attach the PTO shaft, start the tractor and engage the PTO to turn on the mower. Shut it off and see if the marks no longer line up. If they don't you know the clutch slipped.

On my mower there are two small doors on the guard that's attached to the gearbox. Opening them up reveals the tapered bolt and nut that holds the gearbox end of the PTO shaft in place. Remove the nut and gently drive the tapered bolt out, then slide the shaft off. The slip clutch comes with it and the whole thing is heavy.

There are other ways the PTO shaft can be attached to the gearbox, this is one common one. A manual would help and should also give you the specs for slip clutch adjustment.

 

[ovrszd]

Sounds like you know what a slip clutch looks like so we are confident it has one.

I'd start at the blade spindle. With the PTO shaft held from turning I'd try to turn the blade spindle. If it turns, does the gearbox shaft turn? If it does, I'd focus on the gearbox. If it does not, I'd focus on the blade spindle and how it's fastened to the gearbox shaft.

If everything underneath is working as it should then check the gearbox by again turning the blade spindle. Does the gearbox input shaft (the slip clutch is fastened to) turn? If it does, I'd focus on the slip clutch. If it does not, the problem is within the gearbox.

If the gearbox is working, turning the blade spindle causes the gearbox input shaft to turn, the problem is in the slip clutch.

 

[livemusic]

You guys are knowledgeable, thanks for your posts. More info...

I tried to figure it out yesterday and I couldn't determine anything wrong with the cutter and I decided to hook it up. It cut normally! After about 30 minutes of mowing, I needed to move a log out of the way and I put the tractor in neutral, applied the parking brake, idled down, left the PTO engaged, hopped down and moved the log and was back in the seat in maybe 30 seconds. Started mowing and it was not mowing! No matter what I did after that, I could not get the PTO to spin. It seems it is the tractor, not the mower. To engage the PTO on this tractor, there is a button on the right side of the dash that lights up red when engaged. It would light up normally but the PTO would not spin. Is there some kind of safety cutoff that might be malfunctioning?

Let me ask... there is a joystick hydraulic gizmo for the front end loader. I note that the hydraulic fittings on this joystick are super hot to the touch. Is this normal? I can't imagine it being normal for these fittings to be so hot! Is there a temperature shutoff? Do you think it was just coincidence that when I moved the log and went to mow again, it would not mow or does that seem weird?

Sorry, is there something simple I am missing?

EDIT: The hydraulic system for the FEL... am I correct to assume that it is the same system, same hydraulic oil reservoir as for the rear of the tractor? Could this be a hydraulic oil/filter issue?

 

[bearthebruce]

I'm going to ask a stupid question: did the PTO gear lever pop out of gear?

Turn the PTO electric clutch off.
Depress the clutch (if not an HST)
Move the PTO lever out then into gear.

I have had this happen on our Massey. Every time it happens, I have a bright red face because I feel like such a newbie... You would think after spending a couple hundred hours on the tractor, this would be an automatic check on my part. NOT! It's becoming muscle memory.

On the heat of the joystick control.. have you checked the fluid level? I think that the PTO is in the Hydraulic fluid and maybe if low, the electric clutch does not pull in properly?

I don't think there should be a lot of heat on the joystick controls.. when using the bucket and fluid is being pushed, there likely is some heat.. but I would not expect it to be too hot that I might get burned which is what you post seemed to suggest..

These are my random thoughts...

 

[livemusic]

This tractor has an electronic switch, a button you push, to activate the PTO. I do not know if there is a PTO lever, I will look at it when I go back to the tractor. If anyone knows, advise. I need a tractor manual, the seller did not provide me a manual. I got one emailed to me on the Woods cutter.

It seems odd to me that, as reported above, the button WOULD engage and light up but the PTO would not spin.

EDIT: I found a youtube video for a different model Mahindra model, 2538 (mine is 5010), and that 2538 tractor has three different PTO switches/levers. It has the electronic button that lights red like mine has, and it also has a switch below that on the dash, manual/off/auto, and also has a PTO lever on the left side of the seat. So, I will need to look at my tractor.

EDIT: I also found an old post that mentions that there is a solenoid for the PTO under the right floorboard that can be a problem, either a failing or broken wire, or stuck, and that you might be able to free it up if stuck.

 

[cbg8670]

I think you can get manual on mahindra site with tractor serial number. You may try posting issue in mahindra forum someone may have same tractor and help with first hand knowledge

 

[bearthebruce]

I read from the manual online.

Mahindra 10 Series Manual

 

[livemusic]

I read from the manual online.

Mahindra 10 Series Manual

I also had found that manual but it says it is for 6110 model and mine is 5010, so, I do not know if that will apply. I have not found a free manual anywhere for 5010 and I have spent a lot of time searching. I found a download one for $39. I called Mahindra and the lady was walking me through downloading one but at the very end, it said unavailable for 5010, contact your dealer. And I fear that the dealer will charge a big price. The dealer I just spoke with is clueless, will try another.

 

[ericm979]

The auto position on the PTO switch on my Branson turns the PTO off when the implement is raised up and back on when it's lowered.

I don't use it because I like to throttle down to slow the implement down before turning off the PTO to save the PTO brake, and engage the implement at idle then throttle up to save the PTO clutch.

If you leave the PTO on at idle you should be able to hear the mower turning. I can hear mine. So you can tell when the PTO turns off. You can also watch the PTO shaft. Even with full shields you can usually see if the shaft is turning. The shields move some as the shaft turns inside them.