Ballast 7 foot bushhog with 4120

[Gale Hawkins]

I think you're gettin' more Hog than the tractor can eat!!

I'd be lookin' at more pto hp at the very least - the 4120 will be at the "ragged edge" of capability and if the grass is real heavy and/or a wet - the tractor will be working real hard to maintain rpm.

Bigger tractor or smaller mower...

If you can maintain a faster, consistent speed with say - MX6 - how much time would you really save crawling around with your front wheels "light" and your rpm's "challanged" using the 7' Woods??

AKfish

Product Specification for 4120 Compact Tractor (43 hp)

If this is the tractor then I totally agree with AKfish.

35 HP or even if it is manual 37 HP will NOT handle any 7' cutter based on my experience. I like JD from our backhoe experience but pull our HD 7' cutter with a 265 MF with about 60 engine HP and it is maxed out even with weights on the nose.

Yesterday I was cutting fescue with a full head of seed that was not bush hogged last year and cutting about an inch off the ground right behind the church since the owner said we could use it as a place to play during VBS coming up in two weeks.

I was in 1st gear in low range running at 540 PTO RPM and it was a LOAD. The hours on the tractor (got from FIL who bought it new) yesteday was 1265 hours.

I had a 6' Howse on my 45 HP Zetor (very heavy farm tractor) and it was a good match without front weights.

A 7' cutters are heavy duty (even Howse) because of the forces put on them so on that light of a tractor 6' will be the max for safety reasons even if you were only to be cutting 6" of light grass.

We are on a very hilly place and our HD 7' tries to be the tail that wags the tractor. If you want a 7' cutter shop for a 60 HP JD farm tractor if you want green is my suggestion. I have had 5', 6' and now 7'. It feels more like I would expect from a 10' compared to a 6' unit in my experience.

 

[msmud]

Appreciate the thoughtful replies.

The actual weight on the BB84X is 1076# which is going to be a handful, but not so bad as 1250#. I think a smaller 6' cutter would make most sense but I have the feeling that 10 - 12 70# quicktach weights would likely work a lot better than the 970 with no weights and wheels in the air!
As to the PTO HP, what is interesting about the Nebraska tests that have been done on most Deere tractors is that they show 4 - 10% more actual PTO HP than Deere advertises. In the case of the 4320 eHydro, 41.6 HP versus the 39.9 list figure. If this holds true, then the 4120 likely puts out a little more than the 35HP minimum that Woods calls for, but there isn't a whole lot of reserve there.
The adjustment of the hog makes a huge difference as I've found out. Right now, my mom cuts 40 acres with a 5 ' unit on her 3320. If I adjust the deck flat or--heaven forbid, tilted upward toward the tractor wheels--then the machine will bog down in heavy grass at 2 mph but will give a very smooth cut. With the deck elevated just 2 - 3" toward the rear of the hog, I can hit 3.5 ft tall fescue at 4.5 mph + with little problem but with much more windrowing. Depending on how much windrowing I want on my land, I wonder if this is true on the BB84X.
The problem is that on highly varied terrain, you really can't hit medium speeds for very long, so a bigger hog makes a huge difference. My land is much less open than my mom's; there would be a lot of 2 - 2.5 mph mowing no matter what bushhog I choose.
I dont know. That BB84X could be a very expensive mistake.

 

[cowboy_79_1999]

I run a Woods BB72 on my 3520 without any problems. I can mow with or without the FEL installed, without obviously its a bit light on the frontend, but with the Hydro its very easy to control. That being said I wouldn't want any less Horse Power to run that size mower. Good Luck.

 

[msmud]

Cowboy,
Your experience mirrors mine in hiring a man to bushhog my place when it was rough, filled with 1 - 3" pines and hardwoods. The guy who showed up had an open station 3520 with R4s, front end loader, and a rusted 6' bushhog that looked like it had to weigh about 1/2 ton. This guy chopped up everything on the place, backing slowly down steep declines, powering through grass 4 ft tall. It took him 9 hours to clear about 9 -12 acres in this condition.
When I think about how much more operating torque the 4120 has, even about 10% more than the 3720 which is rated for the same 35 PTO, I'll bet it can handle that BB84X at low to moderate speeds. I've got to find a way to test this before I buy.

 

[jenkinsph]

Folks,
I am new to forum and have enjoyed reading it for quite a while. Need to make a decision about buying a tractor for bushhogging about 40 acres of my 100 acres of varied terrain. Have used and serviced my mother's 3320 cab model and 970 OS model for years so have some experience. She uses the 3320 with a 5' model to bushhog about 40 of HER 100 acres--requires 50 - 60 hours per year for two complete cuttings. Looks like I can get a Cab 3320 with frontier 2072 6 foot light duty for nearly same price as Open Station 4120 with Woods Brush Bull 7' model.
My questions are these: although I am reasonably convinced the 4120 will power the 35 hp requirement of the Brushbull, I am worried about ballasting this monster. Do any of you have experience with a 7' hog on a 4120? How much more weight up-front do you think it will take compared with what Deere lists for the MX6? My mom's 970 has no ballast up front and will raise the front end with just a little provocation. Have some years experience with poor ballasting therefore and am trying to avoid this.
Thanks, TIM

Rereading the first post and the other sucessive post you have made in this thread I would suggest a 4520 or 4720 with either an MX6 or MX7. Since you say your property is more conjested. I didn't mention it in the first post I made but one of the reasons I prefer the MX6 is that it fits my trailer where the MX7 doesn't and I move it around a bit.

Ultimately as you get the land cleared up and maybe help out your mom with her property you may find a 4720 with an MX6 and a pull type MX8 would be a good long term plan. Trying to choose the best fit is something you will have to decide.

 

[sunnyside360]

When I think about how much more operating torque the 4120 has, even about 10% more than the 3720 which is rated for the same 35 PTO, I'll bet it can handle that BB84X at low to moderate speeds. I've got to find a way to test this before I buy.

msmud,
Another tremendous factor in HP required is the sharpness of the rotary blades. I'm mowing ~100 acres twice a year here on this old farm that's now just weeds and grass. I also have a few deer food plots I mow 3 or 4 times a year. I do at least 50% of the mowing with a 4320 and 2072 rotary cutter. RC mower blades are typically very dull even when new but I keep the blades sharp with an angle grinder because it is easy to touch up and the 4320 barely works at all. In fact, I'm only running about 1700 engine RPM's, the cut is great and fuel usage is 0.7 to 0.8 gal per hour. I'm sure it will run at much faster ground speeds with engine set at rated ~2450 RPM's.

If you are just cutting field grasses and light brush, there is no doubt in my mind that a 4120 can handle a 84" cutter with proper ballasting and sharp blades. If I was to buy another rotary cutter for the 4320 it would be a seven footer and I'd keep the FEL installed while running it. Good luck with your decision.

 

[msmud]

Thanks for all the input; excellent advice from everyone. Sunnyside reminds me that I've never sharpened the blades on my mom's 5 footer. We're burning more diesel than we need to.

 

[jcalla]

What is FEL?

JPC

 

[beppington]

What is FEL?

JPC

Front End Loader sir :thumbsup:

(even new me knew that so I had to chime in! )

Sure 'nuff there a thread here for abbreviations/ acronyms: http://www.tractorbynet.com/forums/buying-pricing-comparisons/39809-abbreviations-tlas.html

 

[sunnyside360]

Sunnyside reminds me that I've never sharpened the blades on my mom's 5 footer. We're burning more diesel than we need to.

Besides saving fuel, it's a whole lot easier on your engine and PTO because it's not working nearly as hard with sharp blades. I learned that trick from others right here on TBN. I also have a 3720 cab tractor which is used mainly for cutting about 6 acres of lawn in summer and clearing snow from about a half mile of driveway during winter, and it averages 0.6 gal/hr of fuel (year around use) --- just slightly less than the 4320. The 3720 speed is 2000-2200 RPM's with the A/C on in summer and heat in the winter.