DelMorino Flail Mower Power Stall/Clutch?

[ds10]

The tractor is on its way to the dealer (just got picked up). Only other PTO attachment is the snowblower, and, well, there’s no snow at the moment, so it’d be hard to put any load on the PTO with it. The blower is also deep in the barn, behind the loader-mount plow and many other things…

 

[ds10]

The tractor arrived home today (I was on vacation). They tested the tractor PTO with a dynamometer. No issues with the tractor at all. They could easily reproduce the problem with the flail mower. The DelMorino distributor sent a replacement gearbox (apparently the last one in the US) and while they and the dealer were skeptical of a gearbox causing the observed behavior, the mower worked properly today on our perimeter walkway, which had become tall grass since I last got to mow it. Nobody really understands why the gearbox was causing this, and it's not clear if the replacement will suffer the same fate, but it seems it was the cause.

 

[leonz]

I want to welcome you as the newest resident member of the "flail mower nations" from the Great State of New Hampshire.

About your beautiful flail mower built using excellent Italian craftsmanship:

If that unit has a COMER gearbox that is very unusual.

1. The drum as you call it is what is actually referred to as the flail mower rotor.

2. Did you look at the drive belts to see if they had become loose?

3. As mentioned previously you need to slow down in thick brush or take half cuts
of the material as you have a low horsepower mule.

4. The slower your ground speed is in the forward direction the better your beautiful flail mower
will operate and shred the material.

5. If you have room to mow in a spiral pattern you can increase your fuel economy and reduce
brake wear as you will not have to stop, back up, brake, turn around, brake and then drive forward.


I hope the kubota dealer examined the drive belts on your flail shredder for thier condition and belt tension
as loose belts can cause poor performance and excess noise.
please remember that your beautiful flail shredder mower will sound like a vacuum cleaner or shop vacuum
when it is operating well.



Happy mowing

 

[ds10]

I want to welcome you as the newest resident member of the "flail mower nations" from the Great State of New Hampshire.

About your beautiful flail mower built using excellent Italian craftsmanship:

If that unit has a COMER gearbox that is very unusual.

1. The drum as you call it is what is actually referred to as the flail mower rotor.

2. Did you look at the drive belts to see if they had become loose?

3. As mentioned previously you need to slow down in thick brush or take half cuts
of the material as you have a low horsepower mule.

4. The slower your ground speed is in the forward direction the better your beautiful flail mower
will operate and shred the material.

5. If you have room to mow in a spiral pattern you can increase your fuel economy and reduce
brake wear as you will not have to stop, back up, brake, turn around, brake and then drive forward.


I hope the kubota dealer examined the drive belts on your flail shredder for thier condition and belt tension
as loose belts can cause poor performance and excess noise.
please remember that your beautiful flail shredder mower will sound like a vacuum cleaner or shop vacuum
when it is operating well.



Happy mowing

The gearbox now on the unit is a TB-281A, which appears to be from Comer. I'm interested to learn why this would be unusual, since you clearly have knowledge of this. This replacement gearbox is apparently the same model as was on the mower when it was built, and came from the DelMorino distributor in the US.

Before sending the tractor and mower off to the dealer, I did look at the belts, which looked fine, and tried adjusted them with no impact. The dealer did the same.

The issue was evident when the mower was not even in contact with the ground.

Spiral patterns are not an option when mowing a single pass around the perimeter of a hayfield. Our primary use for this mower is to maintain a walking path around the perimeter of the property. Such mowing is a combination of grasses and saplings. The mower is equipped with hammers, not knives, specifically for this role.

 

[leonz]

Greetings from the soggy Fingerlakes,

Short of measuring the amount of backlash between the gear teeth that could create a power loss from excess space between the gear
teeth this is the only reason there would be an issue with the amount of power transmitted from the PTO shaft to the right angle gear and
then to the cross shaft and the V belts to the driven pulley.

Leon

 

[Jack Yuan]

I've got a DelMorino Funny Super 132M flail mower with hammer cutters on my Kubota LX2610. This attachment has hydraulic side shift and tilt. It's been really great to work with. My concern is it has started to develop a pattern where the power from the PTO is interrupted then resumes. I'm guessing there's a clutch in the PTO shaft or the mower itself, and it's kicking in due to load. What's odd is this happens mostly in tall grass and such and not when the mower is eating its way through brush and woody material.

I've uploaded a short video to my YouTube account in which you can hear the sound difference as this occurs. The mower does keep cutting through this, as the hammers and drum have plenty of momentum to keep it spinning. I'm concerned there may be an issue I need to resolve, and am looking for ideas on what I should be looking at to address it. It didn't do this when I got the attachment earlier in the year. I have lubricated the mower, but haven't taken apart the drive shaft yet. The attachment was fitted to the tractor by my Kubota dealer. Given this is my first time owning a flail mower, I'm not even sure if this is just normal, but it doesn't seem like it. Any thoughts or advice?

This is a typical problem on gear box. Only need replace a new gear box, that's all.

This problem is because of the clearance between gears teeth, the gear teeth require proper clearance to match each other correctly. When the gear box is in working, the heat will make gear teeth metal become bigger, then the clearance become smaller, this will cause noise or even stuck the gears, or this noise could disappear after the gear teeth rub each other long time enough.
The gear box factory normally picks up some units gear box from each batch of production, and test these unit by heavy-load. They will not test every unit in this way, and they don't know what the real load when the mower is working, the gear box is assembled manually by skilled worker, but even very skilled worker could make a mistake, or maybe the gear production machine was shocked by unstale electric at one moment and made a bad gear, or maybe there is a gear made by material has some impurity, or....... Life is always full of "surprise".

Anyway, if the gear box factory and the mower factory hear such noise when testing, they will not let it pass testing.

One question, is the noise smaller or gone if you run the mower without any load?