Bush hog pushes tractor?

[LuvMy670]

I was just talking about my new rotary cutter (coming next week) with a friend and we were talking about the slip clutch and it was mentioned that without one that the rotating blade would push the tractor forward even with the clutch disengaged.

How would this happen? I thought when the clutch was pushed in, the PTO would stop, even with a one stage clutch. Didn't know that there was so much to know about rotary cutters. (still don't know if I have a one stage or two stage clutch yet. Guess I have to wait until I get my cutter).

I have never operated one and have read the "experience stories" about watching how the back end travels (as well as the front end) so I don't knock down any fence posts, get tangled in fences, or cut down trees or any other things I want to keep, but being pushed into objects by my own implement is rather unsettling!!!!!!

I feel like I need to go to school to operate this rig!!!!!!
LuvMy670

 

[dgood1]

On some tractors the PTO is driven by the transmission by a gear connection. On these the clutch only separates the engine from the input to the transmission. The only 2 ways to keep from having the inertial force from an implement driving the gears in the transmission is by using either the "one way" or over running clutch or by disengaging the PTO. Trying to do that under load could damage parts.

As to going to school, I think that by reading on this forum the problems that other people have run into and using that knowledge to keep from having the same thing happen to you is invaluable.

Common sense and thinking about the best way to do something can keep you out of a lot of bad situations. Being impaired by exhaustion, drugs, alchohol or being distracted can get you in more trouble than you want to be in.

Enjoy your machine and tractor safe.

Don

 

[Youare]

As Don has already stated the solution is very simple, install an over running clutch between the PTO and the mower. These items are pretty reasonable in price and available at any tractor dealer. They are not costly especially when you consider the cost of running into something without one, or breaking your tractor.

As far as determining what type of PTO and clutch setup your tractor has, can you depress the clutch pedal about half way down which would stop the movement of the tractor but allow the PTO shaft to continue to run? This would mean you have a "live" PTO. The other style is when you depress the clutch far enough to stop the tractor and the PTO shaft also stops.

As far as an education goes you can not ask too many questions of the dealer you got your tractor and immplements from, or here at TBN. /w3tcompact/icons/smile.gif

Randy

 

[normde2001]

You mentioned a "slip clutch" in your post. Don't confuse that with the "overrun clutch". The slip clutch fits on the implement end of the PTO drive shaft and replaces the shear bolt. The overrun clutch fits on the tractor end, however some tractors have a built-in overrun clutch. You would need to check your manuals or with your dealer to see if you have a built-in overrun clutch.

 

[njrqs]

Yep a lot of older (and greyer /w3tcompact/icons/laugh.gif) tractors don't have that built-in over-run clutch.

Any implement with built-in momentum used while driving (slasher/bush hog is the only thing I can think of) needs an over-run clutch to prevent the problem you describe.

My old thing has an over-run clutch that goes on with the shaft to the slasher.

Dealers tell of stories of people going over banks, running into trees etc. without one. You push the clutch and just keep on truckin !!

Cheers

 

[crb478]

What kind of tractor do you have? You may well have a over running clutch built in, and this would keep the bush hog from pushing your tractor. A over-running clutch is a ratchet type mechinism that locks up to turn the pto, but that free spins if the implement turns the pto from built up momentum. As already mentioned you can buy a add an over running clutch if you do not have one, but you will then need to make sure the pto shaft is the correct lift since this adds about 6" to the pto.

 

[RoyJackson]

"still don't know if I have a one stage or two stage clutch yet. Guess I have to wait until I get my cutter"

I expect you'll have a single stage clutch on that 670.

But, you don't have to wait until the cutter comes in. Get a friend or wife to watch the PTO shaft (from a few feet behind the tractor) as you drive in 1st gear LOW. If you can shift the transmission (to 2nd LOW) depressing the clutch ½ way down (and the PTO shaft keeps turning), you've got a dual stage. If you've got to depress the clutch all the way down to shift, you've a single stage.

I did check into converting from a single stage to a dual stage. When the parts prices climbed above $1500...that was the end of the investigation.

Even if you've a single stage...it's a minor inconvenience, really, depending on your usage of the tractor. However, my next tractor will have a dual stage (probably going to be a 790 Deere)

BTW, do you have your Operator's Manual?

 

[Ozarker]

<font color=blue>Dealers tell of stories of people going over banks</font color=blue>

I wish I still had the pictures to post but I lost them in the big crash of 2000 (hard drive crash). My neighbor did just exactly that with his Ford 8N and a Bush Hog.

At the end of the field next to my house there is a 20' drop into the Gasgonade River. It is an almost vertical drop. There is also a but in the bank where we can back our boats into the water and a cement ramp.

He was cutting the field one day and just plain forgot what he was doing, By the time he realized he was too close to the bank it was too late. He bailed off the tractor and just let it go. He managed to grab a tree branch and not go into the river but his tractor was nearly destroyed. It missed the River as well but it did a perfect nose dive into the middle of the cement boat ramp. The tractor was destroyed beyond repair.

 

[njrqs]

OZ

Nasty story indeed but the very reason for an over-run clutch !!

Roy - Not a good test as my PTO shaft turns ALL THE TIME (when no implement connected) from circulation of hydraulic oil or vibration.

It is not engaged and you can stop it with pressure from your boot/hand etc. but it just keeps on tuning no matter whether I am driving or not.

Cheers