rear wheel on bush hog

Glenn9643 · Jun 26, 2004

While I've never used a RFM or MMM on a tractor, I've run the gamut on mowers from Murray to Craftsman and now use a JD 455 23HP diesel with 60" deck. Operators manual for all of them recommended about 1/4" lower in the front than the rear and level side-to-side. I know from experience that this makes a difference in the cut achieved; it seems that the small difference front to rear assists in clearing the cut particles.
Per the manual that came with the bush-hog, the rear wheel can be set to achieve the desired cutting height within the limits of the cutter design. They recommend that the front cutting edge be kept lower than the rear in heavy materiels but state that if used with the unit level front-to-rear it will mulch the cut materiels better while causing more load on the tractor.
Scalping caused by the forward skid plates will occur it the position control is set too low. If the position control is set so that the skid plates are "just off the ground" on level ground I have found that they may scalp occasionally when turning if you are turning on an uneven area.
If the 3pt hitch is leaking down check-chains will remedy the problem. You can buy them for about $40 or fabricate them yourself cheaper.

Freds · Jun 26, 2004

( Rear Finishing Mowers should be level )

Thanks for letting me know that, Roy. I kind of wonder why that is when belly mounts (at least on lawn tractors) say higher in the rear.

Henro · Jun 26, 2004

FredS,

I think what I am hearing here is...

1) You can do it totally wrong like the dealer told you and keep the rear wheel in the air almost all the time...

2) Or you can do it somewhat wrong and set things up so the rear wheel is just touching the ground...

3) Or you can do it right by following the manufacturer's recommendations...which basically means have the rear wheel on the ground most of the time...

Your call, or course... /forums/images/graemlins/smile.gif

have_blue · Jun 26, 2004

( For the mower to be carried properly and function correctly the rear wheel needs to carry all the weight with some slack in the top link. What do you think you are gaining by setting it up wrong? Andy )

Well, I agree. But saying is one thing and doing is another. I get so frustrated when setting up my brush hog I could bite the top link in half! There are 4 parameters that I try to get at the same time: Mowing ht, rear of the deck higher**, wheel firmly on the ground. I can get 3 just fine, but getting all 4 is a real bear. I wind up with the wheel whanging and banging, because I don't have quite enough weight on it.

I am considering removing the 2 big steel straps that triangulate the top link to the rear of the deck, and replace them with adjustable chains. I hope this will make setup easier!

**As discussed in other posts, I always do this for "blade relief". Any cutting tool must have relief, or the blade will keep dragging against the freshly cut grass tips. It robs a ton of horsepower because it's like cutting twice or more. Excessive relief gets you a curved cut, and makes an ugly job. I go for 3/8 to 1/2" relief in the rear on my 6 footer.

Happy cutting! Too rainy here, and the grass is growing 2" a day! /forums/images/graemlins/smile.gif

beenthere · Jun 26, 2004

have_blue
I have such chains on my rotary cutter to allow the rear of the deck to rest on the 'rear' caster wheel, supporting all the rear weight of the deck, as well as keep the height of the rear of the deck constant. The chains are loose except when I want to raise the deck for travel, or a fast corner, or to lift over an obstacle, such as a stump or rock. The chains work very well. They substitute for the steel brace straps that connected the rear of my RC deck to the top link assembly. The straps would bend if the rear of the deck raised too high whenever I would cut in reverse up a steep bank. With the chains, there is no problem cutting that way.

The front of my RC deck is adjusted for height using the lift arms and the position control. If I did not have position control, I would likely use the check chain approach that others successfully use to keep the lift arms from dropping too low (or lower than desired).

MicroPilot · Jun 26, 2004

Hmm, just got my tractor today and had no problems adjusting the RC according to the manual. Rear higher that the front. I had to lower the wheel about 3" (raised the deck) and lowered the unit to get the proper relief, set the travel stop on the 3PT control, and lengthened the top link to get the recomended slack. Cut about 2 acres with no problems.

Newbie question: What is position control? Is this the same thing as draft control? I also read in another thread about putting the 3PT control in neutral position - I've never seen a tractor with this. What would this be?

OkieG · Jun 27, 2004

There are 4 parameters that I try to get at the same time: Mowing ht, rear of the deck higher**, wheel firmly on the ground. I can get 3 just fine, but getting all 4 is a real bear. I wind up with the wheel whanging and banging, because I don't have quite enough weight on it.


Sometimes I don't count too well, but do you have 3 or 4 parameters listed? Would more slack in the toplink stop the wheel from whanging and banging, or does the wheel do that even when it's firmly on the ground?

OkieG

JerryG · Jun 27, 2004

Would more slack in the toplink stop the wheel from whanging and banging, or does the wheel do that even when it's firmly on the ground?
The more weight on the wheel, the less wanking and banging. That is one of the reasons that some use a chain instead of a third arm. /forums/images/graemlins/grin.gif

OkieG · Jun 27, 2004

Thanks Jerry,
My experience is limited to the use of my own brush hog. In other words, I'm still learning. What I've noticed is that with enough slack in the toplink, so weight of the deck is on the tail wheel, there's no wheel banging. Only when the wheel is in that narrow range between being on the ground or in the air does it tend to flop around and be a nuisance.

Once again,...this has just been my experience. My "light duty" BushHog Squealer seems to have enough weight so no flopping occurs.

I wonder if tail wheel design has something to do with it? Wheels with their pivot shafts close to being over the axle would tend to want to shimmy. Less likely if the pivot shaft led the wheel more.

OkieG

stephan · Jun 27, 2004

Well as I read through all the opinions in this thread I couldn't but wonder how I could possibly survive without a wheel on my RC (sic). I use a 5' cutter without a wheel and have done for a couple of years now without issue. I always thought the wheel would be good when reversing, which I do all the time, to stop the cutter from "bunching" up on the 3PL. I though this would be particularly important when reversing up a slope.

Properly adjusted I get no "scalping", little higher at the back, and I set my control to "float" where the attachment just rides on the terrain. Sometimes the skids will dig into uneven ground when turning or pop rocks out of the ground and I was thinking I might replace the bar type skid with some piping.