Horsepower needed for bushogging

[Sunny 4 Acres]

I have bought a massey ferguson 255. It is a 4 cyl diesel 55hp. Would that tractor be capable of powering a 7 foot brushog? I have a 430 case diesel that pulls a 6 foot descently. The only reason I asked is I want a bigger brushog and I think 55hp will be too much for a 6 foot. Please help me out folks. Thanks

 

[Anonymous-0]

Well here's my experience. Pulled a 5 foot with an 8n ford ( 24 hp). It worked it in 12" tall grass. Put the same mower on my ford 600 ( 32 hp ), much easier. So, I think 55 hp on a 6 foot would be a bit much, but you can always trottle down a little too. Check the mowers manufacturer for gear box hp ratings... they all have a hp range recomendation.

 

[Jimmy King]

You should be able to pull a 10 ft with no problem.

 

[wayne2]

As long as it's more then an IH Cub-you and always pull it back to shop with other one!!!!! LOL Wayne

 

[Anonymous-0]

yes you should have plenty of power for that app. as long as the blades are sharp and you are not in too mch bursh.

 

[Anonymous-0]

the 255 should work good with a 6-ft rotary mower, if the gearbox can handle it. Some light-duty mower gearboxes only handle about 40 hp or so. Find out your mower manufacturer's specs. I've got a MF 165 that has similar engine as your 255. I use a Landpride 6-ft rotary mower and it works great. A 7-ft mower may add a lot more front weight, depending on the mower make, so if you got hilly ground you'll probably want to add front weights if you don't have a loader. Some Masseys seem to be nose light, and it ain't no fun feeling nose light while 'hoggin hills. good luck

 

[steveormary]

Should have no problem with a 7' brush hog. Just dont over speed the pto or try to go too fast.

steveormary

 

[Traditional Farmer]

How big of a tractor you need is governed by two things 1)What are you going to be cutting? and
2)What type of terrain will you be going over?
Cutting an old flat pasture that has been grazed heavily a 35HP tractor will pull a 7' bush hog but on very steep land with heavy grass and a few 3" trees than you need 70HP minimum.

 

[Anonymous-0]

You don't want too LITTLE of a horsepower such as to shock load the tractor in the event you run into some really hard to cut stuff.

 

[RAB]

You are looking for us to give you an excuse to buy bigger? It is the operator that overloads a machine.
Your tractor will only produce the full 55 HP with full throttle and the governor wide open as well. The machine should be protected against over-torque by the shearbolt. You could run it on a 150HP tractor if you wanted. It is the inexperienced or thoughtless operator that would overload the machine. The bigger problem is not having enough power available to drive the machine, overloading the tractor and then the machine, as it will lose rotational speed energy and not cut efficiently. Remember, you can own a Ferrari but don't have to drive everywhere at 150mph!
RAB

 

[Anonymous-0]

Can't be too much power in regard to hurting the mower since it must have either a shear-bolt, or a slip-clutch. Main disadvatage is - if the tractor is much more than you need, it won't be anywhere near as good on fuel as a smaller tractor working in its peak torque and efficiency curve.
A 30 horse diesel will run a 5 brush hog and use almost half the fuel a 120 horse tractor will doing the same work.
A 55 horse tractor is just about right for a seven footer for any type of growth. I've used a 30 horse tractor with a six footer and brush higher than the tractor - and it was working pretty hard much of the time.

 

[Tramway Guy]

Diesels are very efficient at light loads compared to Gasoline engines. The reason is that they always take in a full charge of air and use only enough fuel to maintain RPM. If you keep the load at about 80% of maximum, you would be in the ideal range, in my opinion. If you see smoke, then you are wasting fuel.
A larger tractor uses more fuel than a small one doing the same amount of work because it has to haul itself around (heavier), and usually has more parasitic losses such as larger hydraulics, larger fan, bigger alternator, etc.
I run a 5' Bush Hog squealer with a 28 HP tractor---you shouldn't have any problem with a 7' and 55 HP.

 

[Anonymous-0]

You need to check the HP ratings on the bush hog. How tall and thick is the growth you want to mow? Six foot with 55hp sounds ok but lots depends on height of cut as getting rid of material can be another story.

 

[Anonymous-0]

Not true for several reasons. Also, not all diesel farm tractor have wide open air intakes.
Some use pneumtatic governors with butterfly valves in the air take like several of my IH tractors.

Here's some data on one of Deere's most efficient diesels - that does miserably when not loaded down and used for too small a job. At 22 horsepower, an 8N Ford gas tractor is more efficient.

An 8N gas tractor can be loaded to 25 horsepower and run at an efficiency of 11.1 horsepower-gallons per hour.

A John Deere 414 engine when only loaded at 22 horsepower runs at 8.7 horsepower-gallons per hour.

Deere 6603 with a 414 cubic inch diesel - Nebraska Test # 1809

Fuel efficiency expressed in horsepower-hours per gallon of diesel fuel.

Loaded to 101 horsepower at 2100 RPM - 18 HHG
Loaded to 97 horsepower at 2100 RPM - 17.1 HHG.
Loaded to 85 horsepower at 2100 RPM - 16.1 HHG
Loaded to 65 horsepower at 2200 RPM - 15.5 HHG
Loaded to 44 horsepower at 2200 RPM - 14.7 HHG
Loaded to 22 horsepower at 2200 RPM - 8.7 HHG
Loaded to 1 horsepower at 2200 RPM - 6/10 HHG

 

[Jerry/MT]

A rule of thumb is about 5 pto hp per foot of cutting width for grass. The other limitations are the lift capability of the three point hitch to pick up the cutter and then to be able to maintain steering capability with the mower lifted up. Sometimes front ballast is needed for the latter condition.

 

[Anonymous-0]

The 255 will handle 7,8 or even 9 foot mower anywhere you need to mow.

 

[MF#1]

Amen!

 

[RodinNS]

tis true what you say. That Deere engine is most efficient at full power. The sad part is that it'll probably spend most of it's life at a good deal less than full power where it's not one little bit efficient, which is why there's a half dozen other color engines that will stomp all over it for mid range efficiency. At the end of the day nobidy cares how may hp-hr/gal the thing put out. They care about how many gal/hour it burnt, or how much it burnt for the job. If somebody's style is to run around at half load, they're gonna burn a lot of fuel with the Deere... which is about the way it is around here.
One guy I know fairly well has a 2840 that he bought to replace a Ford 8000. Doing the same work the Deere burns half as much fuel again as the 8000.... Now put the 8000 at 2200 and make it work, it'll likely burn a lot more fuel, and mabey be less efficient. Just depends on where they were designed to be efficient.
That said, there's no substitute for having the right size tractor for the job...

Rod

 

[Leland]

In all reality a 6'er is a perfect match for your 255 ,I tried a 7' on one a farm I worked on had and it was a bit much climbing in and out of ditches and on slopes the bigger mower wanted to drag it down hill .be sure to have a good rack of weights on the front as well that helps more than you would belive . And makes sure you have a sturdy ROPS as well .

 

[Anonymous-0]

A 7 foot will work fine for 99% of anything you might have to do. Is your 255 an early or late model? I know the injection pump can be turned up on the 236 inch engines to 60 HP which would make your tractor the same as a 265. I'm not sure about the 203 engine. It would use more fuel however. I run a 6 foot on a 135 with no problems in most conditions. If the grass is really tall and thick you can lift up the 3 pt. and cut it down some and then lower it and do a second cut. A 255 could run an 88 inch flail mower on the back as well as a 74 inch hydraulic driven flail of the side. A 265 could run with a 74 inch hydraulic on both sides and 88 inch on the back. Dave

 

[Mitch Furness]

If cutting civilised grass it will be no problem, if rough heavy stuff it will struggle. It may also be a little too heavy for tractor when lifted on 3ptl, if going in and out of ditches it may get hairy.

Mitch

 

[buickanddeere]

Any combustion process which has an abundance of air passing through the combustion chamber. The excess/unused air just carries heat therefore combustion chamber pressure. Away from the working area of the engine before the heat can do work.
That fuel your paid for is just heating air then blows it unused up the stack.
Some gas turbine engines even have stator blades before the 1st stage compressor to limit airflow at light to mid loads.

 

[Anonymous-0]

I do custom brush hogging with a 7000# Allis Chalmers 175D (4-248 perkins diesel) and it is the best tractor I have found for mowing. I use a LandPride 6 foot mower and it can take all of the 67hp in swamp grass or in the hills. Usually it just lopes along using 1 to 1.5 gallons of fuel per hour. I make $800 to $900 per tank of fuel (19 gallons).

Sure I could use a larger mower, but that means I can fit between fewer trees, fences, rocks, etc., and I would have to go slower...this time of year I like to keep my ground speed up in order to stay ahead of the dust and chaff! Yes these are basically big fans and they kick up a miserable cloud when it's dry out!

I believe a larger diesel (at least to a certain size) is much more efficient than overworking a smaller one and is a lot easier on everything mechanically. I also found that running loaded tires uses less fuel as they act as a big flywheel and help power the mower thru the tough spots.

As to a 7 foot mower, it costs 50% more than a 6 foot, is longer and heavier (so it will scalp more often) and takes more room to turn around and haul on a trailer.....I'll stick to a 6 foot! There's a reason they don't sell many 7 footers! An 8 foot would be a better upgrade as it has twin gearboxes making it much shorter and the rotation of the blades picks up the grass smashed down by the tires.....but it is 4 times the price of a 6 footer and HEAVY!

 

[Tramway Guy]

I knew the Fordson Major uses a Pneumatic Governor, I didn't know about the IH diesels. What vintage are they? There are exceptions to every rule, of course, I was merely comparing 99% of Tractor diesels with 99% or more of Tractor Spark Ignition engines. As far as I know, all gas/LP/Distillate engines use throttle plates. And under part-load conditions,have a higher fuel/air ratio than diesels.
My point about parasitic losses remains...a tractor which is too large/heavy for the job is less efficient than a properly matched one.

 

[Anonymous-0]

My International Harvester B-275s have the CAV inline pumps with pneumatic governors. In regard to fuel efficiency, they test just as well as many other similar sized diesels with wide-open air intakes. B275 has been tested with a 33 horse load and a fuel efficiency of 14.3 horsepower hours per gallon of diesel fuel.
Now compare that to a similar sized diesel with wide-open intake - a Deere 1020 diesel - loaded at 39 horsepower it runs an efficiency of 14.7 horsepower hours per gallon.
Many similar sized diesels with open-air intakes are worse on fuel - e.g.
Allis Chalmers D15 36 horse 12.7 HHG
(I won't list more, there are too many)

One big advantage to diesel - is the fuel weighs more than gasoline - i.e. there is more fuel in a gallon and more BTUs.

My main point was - and is - most diesels are only efficient at certain power loads and RPM ranges. You might have a large tractor that is highly efficient when being worked at 100 horsepower, but the same tractor when only worked at 20 horse is likely to use a lot more fuel per work done - than a smaller tractor doing the same job - gas or diesel.

Didn't think anybody would try to argue that point. Most farmers I've worked with or known - always had small tractors for light work due to fuel efficiency. My neighbor - year ago - bought two brand new Deere 4020s (still has one). He loved the tractors for heavy work, but always griped about what fuel hogs they were on his silo blower which only needs about 20 horsepower. He finally bought - new - a little 30 horse British Allis Chalmers ED-40, and it did the same job on almost half the fuel.

That's why I posted the Deere specs showing what a dog it becomes when not worked hard. And, those specs are with PTO work loads and have nothing to do with excess tractor weight.

Another example is that of electric gensets. If you take a 60 horsepower 20KW genset and use it to make 500 watts, it is highly inefficient. That because the engine is too big for a small job. A little gas generator rated a 750 or 1000 watts max will make 500 watts using much less fuel - than the large diesel genset.