16hp Kubota 3-cyl diesel vs 20hp Kohler v-twin gas

[MaximusGluteus]

Since you guys are quite familiar with diesel engines, how would a 3-cylinder 16hp Kubota diesel, like the one found in the B7100, compare power wise with a 20hp Kohler Command v-twin? If they were in equal tractors, would they be about equal when climbing hills and pulling or would the Kubota walk all over the Kohler?

 

[MagKarl]

I'd say no comparison. HP is not a good measure to establish what's equal. You're still comparing a lawnmower engine against a tractor engine.

Diesels generally spin slower and put out more torque, especially at lower RPM.

 

[North Idaho Wolfman]

I don't have the exact measurements, but a gas motor compared to a diesel motor, HP is not the best # to compare with, torque is a better base to compare the work it can do.
On average a diesel engine will deliver at least twice and much torque per HP, and that's where pulling power comes from!
If you were to take your diesel engine out of your lets say B7100 at 16HP and bolt in a 20HP Kohler you would be sadly disappointed in the pulling power!
You would also be very upset with the amount of fuel you use! I have a Simplicity 3410 landlord with a 10HP gasoline engine and my L3450 with a 36HP engine the L3450 uses 1/4 of the fuel to do the exact same work!

 

[Mikeske]

My comparison is different but does kind of sort of fit this. I had a John Deere X320 with the 22-25 HP Kawasaki engine and it was a good lawn tractor. I recently got a GR2120 with the diesel engine. There is no comparison between the two as the diesel has a lot of torque down low in the running range where the gas engine has to run at wide open throttle. My property is hilly and the John Deere struggled with even the moderate hills as it had a bagger attachment. The Kubota with diesel engine has absolutely no problems climbing the grade and it also has not a problem climbing and that is also with the bagger.

the power and the efficency of the diesel are also a value here as the diesel riding mowing machine is about .5-.75 gallon per acre where my all John Deere was using 1.25-1.5 gallon per acre. I am actually using less fuel and it will take years for the advantage to show but I really wanted to have all my equipment to be diesel and now I have it.

 

[MaximusGluteus]

My comparison is different but does kind of sort of fit this. I had a John Deere X320 with the 22-25 HP Kawasaki engine and it was a good lawn tractor. I recently got a GR2120 with the diesel engine. There is no comparison between the two as the diesel has a lot of torque down low in the running range where the gas engine has to run at wide open throttle. My property is hilly and the John Deere struggled with even the moderate hills as it had a bagger attachment. The Kubota with diesel engine has absolutely no problems climbing the grade and it also has not a problem climbing and that is also with the bagger.

the power and the efficency of the diesel are also a value here as the diesel riding mowing machine is about .5-.75 gallon per acre where my all John Deere was using 1.25-1.5 gallon per acre. I am actually using less fuel and it will take years for the advantage to show but I really wanted to have all my equipment to be diesel and now I have it.

That's exactly what I worry about with buying another gas powered garden tractor. I have an old MTD 990 with a single cylinder Briggs I/C and it struggles really hard coming up my hill, which is about a 15-20 degree slope. When the deck is spinning, the engine barely stays running or shuts off altogether. Even when the deck isn't running the tractor still has a really hard time. The more I read and think about it, the more I question whether any gas powered tractor will be sufficient for this hill.

 

[hodge]

The diesel will have much more torque, it will use less fuel, and it will outlive a gas engine. There is little comparison between the two. If price is close, diesel wins hands down.
Couple that with today's enthanol-enriched gas and how it hurts small gas engines, and I'd go diesel every day.
I pull a 59" Woods finish mower with my B7100, which replaced a Wheel Horse 520-H with a 20 horse Onan and an 48" deck. The B7100 will mow anything that Horse did, faster because of the larger deck, and on a fraction of the fuel. There is no way that Wheel Horse, regardless of how good they are, would have pulled, or lifted, a 48" King Kutter tiller. Diesel is king.

 

[gpreuss]

A thing to consider in all of this is the machine overall. The BX series weighs in at about 1250+ lbs, has 4WD, and will last 30+ years. The GR series diesel mower weighs about a thousand lbs, also has 4WD, and also will last and last. I seriously doubt that either would even know you have a slope. The threads at this forum about any of the small tractors are STELLAR!

 

[Daren Todd]

Got a 20 horse kohler in my riding mower and 15 horse 2 cyl diesel in my little bota. Tractor is between 35 and 40 years old. Lawn mower is 7 and with the ethonal in the gas it smokes a little on start up. I don't have the hills but a really wet back yard. I actually have to bush hog a section of the back yard in the spring because it's 2 soft for the mower. I'm in the market right now for a finish mower for the tractor and will just keep the rider for going around the trees and areas the tractor won't fit. No comparison btw the too engines

 

[MaximusGluteus]

The diesel will have much more torque, it will use less fuel, and it will outlive a gas engine. There is little comparison between the two. If price is close, diesel wins hands down.
Couple that with today's enthanol-enriched gas and how it hurts small gas engines, and I'd go diesel every day.
I pull a 59" Woods finish mower with my B7100, which replaced a Wheel Horse 520-H with a 20 horse Onan and an 48" deck. The B7100 will mow anything that Horse did, faster because of the larger deck, and on a fraction of the fuel. There is no way that Wheel Horse, regardless of how good they are, would have pulled, or lifted, a 48" King Kutter tiller. Diesel is king.

The price is actually my biggest hang up. I've found some really nice gas powered garden tractors in the $1000-$2500 range, and spending less would be nice, but I'd much rather not be disappointed and end up wishing I had spent more to get the Kubota if it's going to be a much better tractor. I'm going to need to pull a trailer up and down the hill loaded with wood, brush, rocks, stone, dirt, etc., so the last thing I need is for the tractor to stall out on the way up. We also till areas for gardens, one of which is on the hill. If I could do that with the tractor instead of the walk behind that would be REALLY nice.

 

[MaximusGluteus]

By the way, this is one of the gas powered garden tractors I've been seriously considering:

http://milwaukee.craigslist.org/grd/4492732885.html


and the B7100 HST 4wd I'm looking at:

http://greenbay.craigslist.org/grd/4487720726.html

 

[Dave_eng]

The comparison between the two is like comparing a tool to a toy.
If you look at engines on recent walk behind snow blowers the engines do not have a horse power rating but do have a torque rating as it is the best way to rate or compare performance on equipment that will be running at fairly constant speed.
Your Craig's List example looks cheap to me. There are not even caster wheels on the deck only a skid bar.
Dave M7040

 

[North Idaho Wolfman]

We'll a comparison of those two are night and day!
The B7100 is a small fully functional 4wd Tractor with a standard 3 point rear hitch and full hydraulic system.
The Power King is a light Garden Tractor or an over glorified lawn mower!

Buy the Kubota!!!!!!

And after you buy come back here and I'll point you to where you can get all the service, parts, and operator manuals for free!

And then go to Kubota.com and get the ROPS Kit for it for a discounted price!

 

[MaximusGluteus]

Thanks for all the help! You guys are making the decision easy lol.

What in particular should I be on the lookout for when I go check the B7100 out today? I know basically nothing about these tractors.

 

[85Hokie]

The diesel will have much more torque, it will use less fuel, and it will outlive a gas engine. There is little comparison between the two. If price is close, diesel wins hands down.


and the diesel has a lot fewer parts , true some parts are more expensive to work on, but a diesels are far better at producing work, most if not nearly all cars overseas run on diesel, they see the advantages much quicker than we do!

In college I had to do long term study on Diesel vs Gas tractors, I not knowing crap bout a diesel, i thought the ol gas engine was the sheaaat !!! Boy I was wrong!!! The cost to run over the short and long time, the diesel is the winner all day long!! And the real kicker is ......you go and buy off road diesel, $3.25 gallon......vs non ethanol gas at $3.95 a gallon.............makes you feel all warm and fuzzy on the inside!!!!!!!!!!

good article on diesels...

http://www.compacttractorreview.com/articles/Diesel-OR-Gas.aspx

 

[Dave_eng]

Have a very good friend with a B7100 from the 1970's. Tough machine.
What many don't know is that the cooling system is a thermo siphon with no water pump. I would try and work it hard to see how the cooling system performs. The charging system is a little different so I would be checking battery voltage when running to ensure it is OK.
Dave M7040

 

[tjd7869]

things to look for when buying, SMOKE! some smoke at starting and shortly after is normal, smoking all the time or from the crankcase vent tube is sign of trouble. other things to check are the fluids, check the levels, color (nothing should be milky, and nothing should be leaking). check that everything that should move dose so with ease, and things that should not move are firmly attached. lastly DRIVE IT dont just look it over in a garage, fastest way to find problems is to get on and go for a ride and play with every lever. and to help you out with your choice, my L-210 was made in 1972 and shows 4500+ hrs on its non working hr meter that could have stopped working who knows when. my ol girl fires right up (altho she can be grumpy about it) and never gives up on any job, i have plenty of tire ruts to prove that.

 

[MaximusGluteus]

Well I went and looked at the Kubota today, and unfortunately I did not buy it as the seller and I could not agree on a price. The snowblower was huge and actually a bit big for the tractor, but it was pretty cobbled, and so was the home made cab. The tractor itself was in pretty good shape, but it there were certain things that turned me off:

- There were paint runs in several places where I'm guessing paint was touched up, along with fingerprints in the paint in spots.
- The rear tires were shot and needed to be replaced.
- There were added on switches drilled into the dash.
- There was loose wiring hanging all over the place.
- Both the engine and transmission were leaking from somewhere.
- The axle pivot was a little loose, although it wasn't terrible.
- The owner didn't have the deck belt tight so when I mowed with it it was slipping like crazy and actually started smoking (I couldn't see it, but my friend who came with me did). I'm sure it would have cut fine if he had tightened the tensioner properly, but I don't understand why he didn't do that to begin with.
- The rear light setup needed a good bit of work.
- Instead of installing a proper battery tie down to keep the battery from bouncing and hitting the hood, he put a leather work glove on top of the battery


The positives:

- It ran GREAT. Started right up, no smoke besides the initial black puff, and absolutely zero blowby from the crankcase breather after it warmed up.
- 4wd worked perfectly.
- Hydro drive worked perfectly.
- 3 point hitch worked as it should.
- Mid and rear PTO engaged and disengaged without issue.
- High and low range worked perfectly.
- The ball joints were all tight.
- Brakes worked like they should.
- All fluids looked were at proper levels and looked clean.


He wanted $4200 for the tractor w/deck, snowblower, and cab. He said he had an offer of $700 for the snowblower, which was cool with me because after seeing it I wanted nothing to do with it (or the cab, for that matter). Taking into account that it needed tires and some other work, and that I'm sure I'd find other stuff it would need once I dug into it, I offered him $2500 cash. He said he already had an offer of $3600 from someone else for just the tractor and deck and wouldn't go any lower than that. I sat in my truck and thought about it for a few minutes and then left. I wanted very badly to buy it because that tractor was downright AWESOME, but I figure for $3600 for just the tractor and deck it should be in a lot better shape with good tires and without all the half-arsed electrical work. Maybe I made a mistake, but I feel good about walking away from it. I'm really hoping I can find another one though because after testing that one out I'm completely sold on Kubota SCUTs!

 

[tjd7869]

well if the tractor just didnt feel right then you made the right choice walking away, i cant speak on if the price was good or not. but when you sit on the "one" for you. you will just know.

 

[MaximusGluteus]

I LOVED driving it, but I just couldn't get past the idea of having to deal with someone else's cobbled mess. I figured I'd probably end up sinking another $1k into that thing, so I think finding a better one is the smarter idea. I'm just hoping I cross paths with a good one sometime.

I'll never understand people who cobble and half-arse the things they work on. It takes much less time, effort, and money in the long run (and often times in the short run as well) to just do things right the first time rather than having to undo a mess and redo it correctly a second time.

 

[ipz2222]

Maxim. Spend a little more and get my bx2230 that you don't have to do anything to . AND , it has an rops with canopy and a front end loader. And a 54 inch deck, AND fully serviced with all synthetic fluids. There's more (AND"s), but you get the picture. It's in the classifieds here and on craigs list(Chattanooga Tn).
But to your original question. My wife has a Bad Boy 60 inch 30 hp gas zero turn mower. In 1 hour of mowing, my bx diesel will use 1/2 the fuel her's does. I have specificly done a test to verify that.