What side to put the Shear bolt yoke on tractor or gearbox

Rdrett

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If I install my driveshaft with this shear bolt yoke on the gearbox side it hits the plastic cover and will not lock into position.
If I install the driveshaft with the shear bolt yoke on the tractor side it hits the metal PTO cover.
What do I do?
 

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North Idaho Wolfman

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I would say 2 options come to mind:
1: Find a better shear bolt / drive shaft setup, like maybe a slip clutch.
2: Alter the Flail side to get it to clear, I wouldn't touch the tractor side of things.
 

Dave_eng

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COMER, a big manufacturer of PTO shafts and other products for the Ag industry, says the shear bolt belongs on the implement end.

See this message from Chris at COMERINC.com
The protection device is usually on the implement end. The torque is driven by the implement and you want to protect the gearbox.
Thanks,
Chris

Is this a brand new flail?

Did the pto come with the flail and is there any pto brand info
Dave
 
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Rdrett

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COMER, a big manufacturer of PTO shafts and other products for the Ag industry, says the shear bolt belongs on the implement end.

See this message from Chris at COMERINC.com
The protection device is usually on the implement end. The torque is driven by the implement and you want to protect the gearbox.
Thanks,
Chris

Is this a brand new flail?

Did the pto come with the flail and is there any pto brand info
Dave
I also thought that the shear bolt should go on the implement end. Most everything I have seen was set up this way. Shear bolt or slip clutch on implement side.

Yes it is a brand new Chinese flail:eek:

Yes the flail mower came with the PTO shaft and the shaft was manufactured by ARGI-MACHINERY.
 

Dave_eng

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I also thought that the shear bolt should go on the implement end. Most everything I have seen was set up this way. Shear bolt or slip clutch on implement side.

Yes it is a brand new Chinese flail:eek:

Yes the flail mower came with the PTO shaft and the shaft was manufactured by ARGI-MACHINERY.
Another issue often not address by owners of pto driven implements.

Correct pto shaft length. Too long and you can destroy the rear of your tractor by the intense pressure put on the tractor as you raise an implement and the shaft bottoms out. Sometimes what you hear is a sickening loud crack as casting(s) fail.

Too short and you risk either damage to the shaft as it needs sufficient overlap to transmit the torque. Way too short and it can come apart and become what I refer to as a medieval weapon of war as the tractor ends flails wildly around.

I may be going on about things you already know but I prefer to be overly cautious.

The safety chains on either end of the pto shaft shield are very important. They ensure the shield is stationary even when the shaft is turning.

Some youtube videos worth watching
Dangers:
https://www.youtube.com/watch?v=f7BVNqFi_So

Safety chain length
https://www.youtube.com/watch?v=IdGbJNbVHwA

Length:

https://www.youtube.com/watch?v=MOr7KZUoEkc

Don't be afraid to pull the two halves of the pto shaft apart. They are designed now to only go together the correct way to maintain joint phasing.

Dave
 

Rdrett

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Thanks for the advice.
I do not know what to do.
I was thinking about removing one of the safety shields but after watching the video I changed my mind.
Does anyone know where I can get the correct size shield?
I can find places all over the world who sells them but no where in the United States.
My only option is to find the correct shield or make one.
Any idea, I am lost.
Unbelievable the new flail mower does not have comparable parts..
I wish I would of spent the extra grand and got a woodsmax.
 

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Dave_eng

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Thanks for the advice.
I do not know what to do.
I was thinking about removing one of the safety shields but after watching the video I changed my mind.
Does anyone know where I can get the correct size shield?
I can find places all over the world who sells them but no where in the United States.
My only option is to find the correct shield or make one.
Any idea, I am lost.
Unbelievable the new flail mower does not have comparable parts..
I wish I would of spent the extra grand and got a woodsmax.
Is the oval shield you posted a photo of metal or plastic?

Can the black shield go onto the flail with the oval in the opposite rotation than the one you have tried and found a problem. Example: If before, the shield had its widest dimension in a horizontal plane, can you rotate it so that the widest dimension is now vertical? Does this improve the interference situation?

Could you plse post some photos of the flail shield and the pto together so the interference can be better understood and then suggestions can be made.

I big hammer fixes many an incompatibility when farm machinery is involved.

If the oval part in the photo is metal, it can be easily deformed to provide the necessary clearance. Wont be nicest looking modification but very workable.

I have been looking at your model of flail mower on line and the pto shield or guard appears to always be round yet your photo looks oval.

Don't give up there will be a solution.

I am very pleased you took the time to look at the youube video on the dangers posed by pto's. Many a novice sees it rotating at a slow speed is unaware of just how dangerous they are.

Dave
 
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mcfarmall

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The shear bolt is an overforce mechanism plain and simple. Its one and only job is to protect downstream components from damage. Typically it is located just ahead of the gearbox as others have stated.

If it was positioned at the tractor end, all components downstream will be protected, the u-joints, the shaft, the gearbox, etc..

I take a more risky (to some) approach to driveline safety. At the tractor end, when the implement is in use, are you likely to come in contact with an unshielded u-joint? You have the top link, both 3PH lift arms, 2 draft arms, all the structural steel of the implement hitch, etc. all preventing you from contacting the rotating shaft easily.

On the implement end, there fewer obstacles between you and harms way. Are you or any other person going to be standing with their toes under the flail mower and within reach of the driveline while the PTO is engaged...let's hope not.

Using this logic, if it was my tractor and my dilemma, I would remove the guard on the tractor end and leave the shear bolt where it is.

If you were pulling a hay baler from the drawbar, the driveline would be more exposed and I'd be much more concerned about accidental contact with exposed components.

Everyone has an opinion and now you have mine.
 

ItBmine

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I have the same clearance issue with my Wallenstien BXM32 chipper/shredder. I had to raise the guard on the chipper end so that it didn't hit and go bang bang bang when it was running, LOL.
 

Rdrett

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Here is the Implement input guard cone that came with the mower.

See how the shield steps down to a smaller diameter?
The knuckle on the shear bolt yoke hits where it steps down and will not allow the shaft to slide on far enough to lock onto the gearbox.
I need a cone that doesn’t steep down and is the same diameter.
I would like to find something like this.

Unbelievable that I cannot find one in the United States, such an important piece of safety equipment and I cannot easily find one.
I might have to order one from overseas.
 

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Rdrett

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Paris Ky
And the arrow is pointing to


So the dealer I purchased the mower from was correct in saying that the shear bolt yoke go to tractor end.
 

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