brush hogging problems

[mf180]

Before today I had never brush hoged before. Just bought a used 6ft bush hog. I didn't really know how to set everything up just tried to get the deck level. I wa cutting about waist high weeds and grass and it would do fine for a while then the deck would start shaking violently. I would stop and it would keep doing that for a few seconds then be fine for a while and start shaking again. Any ideas dull blades, adjustment problems, rpm, any ideas would be greatly appreciated.

 

[EastTexFrank]

Before today I had never brush hoged before. Just bought a used 6ft bush hog. I didn't really know how to set everything up just tried to get the deck level. I wa cutting about waist high weeds and grass and it would do fine for a while then the deck would start shaking violently. I would stop and it would keep doing that for a few seconds then be fine for a while and start shaking again. Any ideas dull blades, adjustment problems, rpm, any ideas would be greatly appreciated.

Mowing too fast, slow down. The blades might need sharpening but basically you're overloading the deck. It can't clear the grass quick enough and the blades get out of whack and cause vibration. The blades aren't fixed as on a finishing mower and can pivot. This is to allow them to hit some immovable object and pivot out of the way and not cause it to stall, break or some other bad stuff. If you overload the deck, the same thing happens, the blades move out of alignment, the whole set up gets unbalanced and causes vibration, clattering and banging. When you stop forward progress it gives the blades the opportunity to clear the grass from under the deck and things settle down. If you look back you should see a clump of grass being thrown out. If you slow down, give the mower time to clear the grass it is cutting, things will go smooth.

Also, make sure the PTO is turning at the recommended speed for the mower. Most rotary cutters are geared to cut best when the PTO is turning at 540 rpm. Some tractors have a PTO that turns at 1000 rpm and the mower must be geared accordingly or else you are going to overspeed the mower and it will self destruct in short order.

 

[greenmule]

Probably as was said,but my 7 year old kk will vibrate pretty bad sometimes,blades don't stay in right spot I guess,this happens when backing up and slowing pto down to shift gears,think things/blade bolts,are getting worn,but it never happens when I get going even in thick tall stuff,so since you said used,maybe yours have some of same problems?I can get it back by stopping,letting it slow down by pushing clutch all the way and than poping clutch out. If you keep rpms up,the only reason it should maybe shake is like was said though.

As far as setting it up,raise it till its about 4-5 inches high all around from bottom of deck with tailwheel on ground,I use a chain instead of top link,thats about all there is too it.

 

[Farmwithjunk]

With the FRONT of the deck set at proper cutting height, set the tail wheel so the REAR of the deck is 1" to 2" HIGHER than the front. With the deck set level, the blades often have to cut everything twice. With the rear higher, clippings exit without plugging the blades. All around, results will be better.

 

[jinman]

I'd like to add one more suggestion to the terrific advice you've already received. I think you need to raise the cutter as high as you can get it on your 3PH and do an underside inspection. Put blocks under the cutter in case the 3PH drops and then crawl under there and check the stump jumper to make sure it is tight and not able to wobble on the output shaft of the gearbox. Also check that your blade bolts are not coming loose. The blades will have a little up/down play, but it should not be excessive. Normally, you also have inspection ports on the top of the cutter where you can look at the blade bolts/nuts to see that they are tight and both the same. Also, look at the bolts holding your gearbox onto the body of the cutter. If these are loose, the whole gearbox, stump jumper, and blades can jump around under load.

Probably everthing will be fine, but you'll have the extra confidence of knowing that everything is tight and nothing is coming apart on the underside of your deck while cutting brush.

 

[greenmule]

My results are excellent too,when deck is level by the way,on my kk cutter if you had rear 2-3 inches higher than front,your front would be 1 inch or so from ground and dig in,[yeah I know rear wheel goes up and down],I got it in its next highest setting,and thats what would happen,plus no need of doing it,my ck30 doesn't lug one little bit in 4 ft tall orchard grass with my 5 ft cutter.And it doesn't appear I'm cutting it twice either,behind cutter you got this nice wind row of grass that is just as long as it was but laying down,so that part of this[cutting it twice] is a myth,in my case.

 

[Farmwithjunk]

My results are excellent too,when deck is level by the way,on my kk cutter if you had rear 2-3 inches higher than front,your front would be 1 inch or so from ground and dig in,[yeah I know rear wheel goes up and down],I got it in its next highest setting,and thats what would happen,plus no need of doing it,my ck30 doesn't lug one little bit in 4 ft tall orchard grass with my 5 ft cutter.And it doesn't appear I'm cutting it twice either,behind cutter you got this nice wind row of grass that is just as long as it was but laying down,so that part of this[cutting it twice] is a myth,in my case.

Hate to break it to you, but your idea of a "Myth" is the accepted way to set up a mower PROPERLY. Not MY idea, but that of a few rather noteworthy manufacturers in the field(such as; Bush Hog, Shulte/Alamo/Rhino, Woods, Landpride, ect....)

Setting the rear UP doesn't lower the front. You set the FRONT with the 3-point hitch/position control. That height stays constant (if you have a tractor with adaquate position control). Rear deck hight is set with tailwheel. If front height is set correctly, skid will be no closer to the ground with rear raised slightly.

Not a guessing game on my part either.....Based on a BUNCH of hours of real world experience. I own a commercial mowing business. (Mow highway right-of-ways, commercial real estate, ect) With contracted work and the equipment I have on the job, it's expected that we'll log somewhere in the neighborhood of 11,000(+) hours of mowing this year alone. All the mowers, from 6' mounted models to 15' batwings are set with rear slightly higher. They simply CUT BETTER and DO A BETTER JOB that way.

 

[greenmule]

Yeah well we both know what we're talking about than cause so do I,I been hoging on a tractor for 30 some years off and on,so..

On a kk [like I've said but will say it once more],if you set tail wheel to its highest postion[rear of mower being at highest postion] and you want front to be 3-4 inches lower[yeah know how three point works,but thanks],your front will be about touching ground,least on the one I got now.Than when you mow on unlevel dippy ground,your fronts going to dig in,alot.

I also know what the books say.

Plus,like I said,no reason to worry about this at all, my ck30 goes through 4 ft tall thick,damp orchard grass,lays it down behind me in one piece,doesn't lug motor a bit,so,just make it easy on your self and set it about level all around. Maybe a finish mower[which I ain't got] yeah,front lower than rear,maybe if your hog was to big for your tractor,yeah,but on my 5ft hog with ck30,no.

 

[sandman2234]

I would tend to think that "Orchard grass" would not be as thick due to limited sunlight as the open right of ways on interstates. Unless you are pushing a bush hog or the tractor to it's limits, it really doesn't matter how you hang the hog behind the tractor. My experience with an underpowered tractor and a light weight bush hog taught me to try to give the grass/brush/trees somewhere to go once they were cut, which means raising the rear of the deck just a little higher than the front. FWJ probably has more hours in the seat in front of a bush hog this year than I have over the last 30, but why should anybody listen to him??? Back to my soapbox...
David from jax

 

[SPYDERLK]

On a kk [like I've said but will say it once more],if you set tail wheel to its highest postion[rear of mower being at highest postion] and you want front to be 3-4 inches lower[yeah know how three point works,but thanks],your front will be about touching ground,least on the one I got now.Than when you mow on unlevel dippy ground,your fronts going to dig in,alot.

You make a real good point against the KK. When you cant set a bushog up right it cant work its optimum. Sounds as if, somehow, the KK has been designed so that it cant be set up right.
larry