Brush hog blades stopped turning

[Joe)NYC)]

I was brush hogging when suddenly the blade hit a rock. After that blades no longer turned. The brush hog is an older unit and cannot find any identification on it. Since I cannot describe make model etc, in general where should I look to find the broken shear pin or bolt, or whatever else could have broken. If it is a shear pin or bolt, how do I remove it and what do I replace it with?
Thanks for any info.

 

[Dell (WA)]

Joe......yup, sounds like you sheered the sheerpin. Thats what they are for. Usually a bolt in the "U-joint" next to the gearbox. You may haffta take them plastic OSHA safety covers off to find it. replace with grade#2 bolt of correct diameter and length. Simple, eh? ......Dell

 

[DanH01]

Can you post a picture? No shear pins that I know of. If your PTO is engaged the shaft and blades should turn. Unless something broke with the PTO or the gearbox of the bush hog. Disconnect the driveshaft from the PTO and with the tractor in neutral engage the PTO to see if it turns. If it does then see if you can turn the driveshaft by hand and turn the blades. if they won"t turn then the problem is in the gearbox. Are you sure the PTO didn"t just jump out of gear? That can happen.

 

[Joe)NYC)]

Thanks Dell and others. When the blade hit the rock it no longer was cutting. When it happened I stopped the tractor(in neutral) while the PTO was still connected I could see the drive shaft turn(which is good) but the blades were not spinning as I could not see any grass motion or hear the usual 'whoosh' of air. The tractor is 240 miles north of me and probably won't get to work on it till next Spring. It gets too rough for me in upstate NY in winter.

 

[souNdguy]

if the drive shaft to the gearbox was spinning, but the blades weren't turning, then I'd look right there where the driveshaft hits the gearbox input shaft.. many times the input shaft is round and is held tot he driveshaft with a soft grade 2 bolt and a split ring.. onc ethe bolt shears, the ring keeps the driveshaft on the input shaft.

it's a VERY common setup.

soundguy

 

[souNdguy]

not sure where you've bene the last 50-60 years.. but a SHEAR PIN setup at the driveline to input shaft on the gearbox is a VERY COMMON setup.

soundguy

 

[DanH01]

Where I"ve been is a 12 hr workday 14 hr round trip. And I guess the shear pins I had in mind, and didn"t recall seeing on my bush hog, were something similar to what we have on our presses, which at a quick glance would work on a bush hog.

 

[JMOR]

(quoted from post at 06:47:56 11/06/09) Where I"ve been is a 12 hr workday 14 hr round trip. And I guess the shear pins I had in mind, and didn"t recall seeing on my bush hog, were something similar to what we have on our presses, which at a quick glance would work on a bush hog.

here are different implementations, such as this one thru two flanges, one on the gear box shaft & one on drive shaft/u-joint. There are others that use a spring loaded friction clutch to allow slippage.

 

[rmlarsen]

My Woods has a "shear bolt" in the driveline to protect the gearbox. Yours probably has something similiar. It's the old "break a $2 part to save a $200 part" theory.

 

[souNdguy]

Yep.. I've been working 2 jobs for 10ys now.. ain't fun at the end of the day.

soundguy

 

[oldroosterman]

Joe......yup, sounds like you sheered the sheerpin. Thats what they are for. Usually a bolt in the "U-joint" next to the gearbox. You may haffta take them plastic OSHA safety covers off to find it. replace with grade#2 bolt of correct diameter and length. Simple, eh? ......Dell

I have the same problem I treaded for an older 6ft Buch Hog the drive shaft turns but the blades won't they are a round cover over the bottom covering the blades.
Are they a shear bolt under it.

 

[oldroosterman]

I have the same problem I treaded for an older 6ft Buch Hog the drive shaft turns but the blades won't they are a round cover over the bottom covering the blades.

Are they a shear bolt under it.

 

[Jim.ME]

I have the same problem I treaded for an older 6ft Buch Hog the drive shaft turns but the blades won't they are a round cover over the bottom covering the blades.

Are they a shear bolt under it.

Welcome to the forums.

I don't know if you noticed but this thread is from 2009. A couple of these fellows have passed on, and the others have not been around for years.

You should start a new thread of your own about your "buch" hog. You need to post some pictures of it, especially the driveline. There are many, many such cutters out in the world, not all are the Bush Hog brand and different drivelines were used, so it is very hard to tell you about yours without seeing it.

 

[oldroosterman]

I have the same problem I treaded for an older 6ft Buch Hog the drive shaft turns but the blades won't they are a round cover over the bottom covering the blades.

Are they a shear bolt under it.

It covers all I can't see if they are.

 

[soaked]

Hi oldroosterman,
Im not understanding a "cover over the blades"
This squeeler has a low grade bolt that has sheared off before...

The blades can pivot 360° around the stump jumper the gear box turns...

 

[Ray,IN]

I have the same problem I treaded for an older 6ft Buch Hog the drive shaft turns but the blades won't they are a round cover over the bottom covering the blades.

Are they a shear bolt under it.

This long-winded video shows where the shear bolt is and replacing the bolt by a novice.

 

[Eman85]

As stated you should start your own thread.
Just a public service announcement if you didn't know don't put just any old bolt in there be sure it's a soft shear bolt. If you have rocky land or stumps or whatever buy a few when you're there. If you put a grade 5 or 8 bolt in there you might find out how much a gearbox costs.

 

[Ray,IN]

It covers all I can't see if they are.

Stump jumper on a King Kutter mower is designed that way. Nothing to see behind there anyway.

 

[Tall T]

I was brush hogging when suddenly the blade hit a rock. After that blades no longer turned. The brush hog is an older unit and cannot find any identification on it. Since I cannot describe make model etc, in general where should I look to find the broken shear pin or bolt, or whatever else could have broken. If it is a shear pin or bolt, how do I remove it and what do I replace it with?
Thanks for any info.

You might be thinking that the sheer pin is some special part like on an outboard propeller,
but it is just a low grade bolt that passes through the coupling that you put a normal nut on.
Like the guys have pointed out, just make sure the bolt is a grade 2 (low grade as per sheer strength).