Bush Hog: Round vs. Oval Stumpjumper

[PM1]

I have a Bush Hog SQ720 rotary cutter that's sold as a "light-duty" mower. It's served me well through 3 years of serious abuse. Although the manufacturer specifies the cutting capacity as 1.5 inches, I've often used it on 4-inch saplings and heavy brush. I've also hit countless logs and other obstacles, and I routinely hit 30 or 40 stumps when mowing parts of my property. I've even broken off a blade while mowing (yes, they can break).

The SQ720 has an oval pan, or stumpjumper, covering the blade holder bar. That oval pan has finally bent enough from hitting stumps that it's beginning to keep the blade from swinging freely. The replacement part is over $300, or about 20% of the cost of the mower. Replacing the pan and blade holder also means I'll probably spend a full Saturday with a sledge removing the old and installing the new -- if I'm lucky.

All heavy-duty mowers seem to have stumpjumpers that are round instead of oval. That would seem to be a better design for avoiding stump damage. Does anyone have experience with both oval and round stumpjumpers? If so, is the round significantly better, or does it eventually get destroyed by stumps as well?

Since there is no round stumpjumper option for my mower, the only way I could get a round one would be to buy a heavy-duty mower. It might be worth considering if a round stumpjumper would last much, much longer than the oval I currently have. If a round one won't make that much difference, then my best bet is to make the repair and try to make it last another two or three years.

I appreciate any advice or experience.

Parker

 

[Soundguy]

I don't think the round stump jumper is limited to the HD mowers. My 5' KK mower is a light/medium duty mower.. economy for sure.. it has a round stump jumper. My howse heavy duty ( economy brand ) has a round stump jumper... Mj JD batwing has no stump jumper.. jus tthe blade carrier /forums/images/graemlins/shocked.gif

In any case.. i think hitting stumps is what eventually does them in.. round or oval... you hit 40 stumps at 540rpm..and something gives eventually...

Soundguy

 

[Highbeam]

My light duty Rankin's stump jumper is round too. I recently took my stump jumper off since it had bent from brush mowing much as you describe, well not mowing 4" "saplings" but hitting stuff, and the blade tips were notably closer to the deck then they should be.

I removed the blades and then the stump jumper and set them on the workbench. There were some cracks and obvious bending of the carrier/stump jumper assembly. I set the assembly between two blocks of wood and beat it straight with a sledge. This is a piece of metal and at 300$ I would try and bend it straight before buying new. It actually was very easy to true up within the accuracy of my measuring devices and a straight edge. The stump jumper pan had begun to seperate from the carrier so I welded it back together and ground it smooth where the blades needed to swing.

I mowed about four acres with it over the weekend. Good as new.

I also have to question why anyone would pay 1500$ for a light duty mower. The other brands like Howse and KK are available for less than half of that. Maybe the paint is really nice.

 

[Farmwithjunk]

I'm not so sure you didn't already answer your own question. You commented on how much abuse the OVAL pan took over the years, then asked what, if anything, is wrong with that design. If it took that abuse on a light duty mower, why not buy ANOTHER just like it?

I've got a Bush Hog 286 and a Woods BB840. Both with round stumpjumpers. Both considered "medium duty". Both take a thrashing. Both take the abuse in stride. Both will finally get beat up and wear out.

If you routinely hit stumps and big rocks, you'll be bending any mower made finally.

BAck in the day, there wasn't all this "light duty" medium duty" and "heavy duty" stuff with bush hogs. We just cut anything the tractor would shove over and bought a new mower every few years. Now we have choices.

 

[FamilyFarm]

I agree 1500 should buy more than a light duty cutter, but also the duty ratings are all over the place with each manufacturer. It sounds like the one he as that is called "light duty" is probably as tough as many that are called med duty. While 1500 still sounds high, it would probably take well over a grand for most that would stand up to that much abuse - take out those stumps or raise the cutter a little!! /forums/images/graemlins/wink.gif
Terry

 

[john_bud]

He He he,

Farmwithjunk has a great point! You are the poster child for that mower! It sure took a lick'n and kept on tick'n! Before you spend $300, do try and bend it back straight. Given what it went thru, it probably has some cracks. If you don't have a welder, you can get simple repair welds done cheap. Just use a wire brush and grinder to clean everything up nice. Less work on their part, is less money spent!

jb

 

[Soundguy]

</font><font color="blue" class="small">( but also the duty ratings are all over the place with each manufacturer. It sounds like the one he as that is called "light duty" is probably as tough as many that are called med duty. )</font>

The manual for my JD 1517 batwing mower classifies it as a light duty mower -ONLY- .. go figure. It's not a finish mower either...

Soundguy

 

[djradz]

Why not have a new piece made. With nothing more than a rough sketch, most metal fabricating shops can come up with something pretty cheap. If you make it from a piece of 1/4" or 3/8" plate, and them have them weld a collar on, and then punch a couple of holes, I think you'll be all set. I can't imagine it costing more than $100, and I would bet it might be closer to $50-$80.

 

[sandman2234]

djradz,
Have you priced steel lately? It has gone thru the roof!
If he is lucky to find a shop with a small drop, and something to bend it with, he might get it for that price.
You never know till you ask.
David from jax