Rotary Cutter 6 ft rotary to big?

[kempryan28]

Hello all. I recently got a great deal (to good to pass) on a 6 ft priefert rmx600 it痴 a 6 ft rotary deck. However the thing is giant, a lot bigger that I though it would be. I have a yanmar 276d with a 27 hp engine and 23 hp to the pto.

The recommended hp for the deck is 40+ no more than 60. It has a 540rpm gearbox and my tractor has both 540 and 1000 pto options. Is my tractor going to be able to handle this thing or should I sell it and downsize?

I run a 6ft snow king blower with no problems... and am generally comfortable pushing my tractor a bit to get the job done.

What are the ramifications if I try to run it and it hurts my tractor... I would imagine I could hurt my gearbox and pto... thoughts?

Thanks in advance!

 

[cglaser104]

Can you run it? Sure. 540rpm is the same regardless of horsepower behind it. Realistically your probably doomed to lighter grass cutting as maximum expectation. General rule of thumb is 5hp per foot of cutting width.

There is almost surely some driveline protection whether it's a sheer bolt or slip clutch. So long as it has the right sheer bolt in place or a properly adjusted slip clutch it shouldn't hurt the tractor. One concern might be the overall weight of the unit vs your lift arms and the weight of the tractor. It might make you light up front which will affect steering/manueverability.

 

[RickB]

I'd be more concerned about lifting and handling the weight than anything. After the first pass you don't have to take a full width cut. Overlapping can help pick up the grass run over on the previous pass.

 

[CoyPatton]

Several concern areas.
HorsePower— someone mentioned 5HP per foot. From what I was taught as a kid on the farm was 6 engine HP/foot or 4 PTO HP/foot. At 23 PTO HP you are just under the minimum if this old rule. The problem is you are quite a few HP under the rule for engine HP and HP recommendations for the mower.
So based on HP ratings, you can probably handle it, but not at optimal performance especially in thick/heavy growth situations.

Weight—
You really did not provide any info in this regards. You will need to lift your 3ph and move from time to time. While some added front weight is normal, if the weight of the unit is stressing your 3ph lift capabilities or causing excessive added front weight or compromising steering capabilities, the unit is too heavy for your machine.
As to what you decide to do as far as keeping or finding a different mower, that is for you to decide.

 

[kempryan28]

Thanks guys. It does have sheer bolts so I should be good there. It痴 weight is 729lbs. I do have a loader up front to balance things out a bit and if needed could scoop some dirt to make it heavier.

So it sounds as if I go smaller I could do bigger jobs such as sage brush etc instead of just light grass with my tractors HP, is this a correct assumption?

 

[Slowpoke Slim]

I don't see how it could "hurt" your tractor. Worst case is it bogs your engine down and if you don't slow down when the bog starts, it kills your engine. Not really a big deal, switch off pto, restart engine and go (but slower). Thick, heavy grass will be harder to deal with than open brush and weeds. I'm at 32 pto hp with a 6' mower, and most of the time I don't have to slow down at all. If the grass is really thick, and gets about hood high or higher, I may have to slow down some. It also depends on how rough the terrain is, as I'm not one to fly around like an idiot across some pasture, just to see how fast I can drive across it. Most of the time it's not a problem.

As long as you're ok with slowing down your ground speed when needed, I think you'll be fine.

 

[MF243RedTop]

I personally wouldn't use a 6 foot cutter with anything less than a 35hp tractor.
The golden rule for the right tool for the job applies here. Taking a 6 foot path through heavy overgrown grass or brush with your current tractor, would be at a crawl IMO.. 5' cutter would be more suitable for your size and weight, probably will do a better and faster job.

 

[Sawyer Rob]

I personally wouldn't use a 6 foot cutter with anything less than a 35hp tractor.

I wouldn't either... (35pto hp)

A shear bolt that designed size wise for a 40 hp on up, will be sized too big/strong for a small 20 something hp tractor, so I'm not convinced it will save the drive line in a little tractor...

I have two 6 foot cutters, I wouldn't want to run either one on a 25 hp tractor!

SR

 

[dodge man]

You have the mower, you have the tractor, try it out. You will probably know right away if it will work out.

 

[ruffdog]

I had a 6 footer on my TC33D and it would handle mowing a field of grass ok but once I got on hills and maneuvering around, it was too big. The OP is right, a 6 is way bigger than a 5 if you are right on that size break. Do what I did, sell it and get a 5 ft cutter.