Kubota B21 low PTO horsepower

[Connor]

Not trying to make a huge difference,
But does anyone know why the B21 only had 13 PTO horsepower?
When other 20 horsepower tractors are in the upper teensIs it the gearing or the extra weight?
I’d like to find a way to turn the power up just a couple horsepower-have a 3 point snowblower and it bogs in heavy snow. Lowest gear in the hydro.

does the B21 have different gearing than others?

 

[Dave_eng]

Not trying to make a huge difference,
But does anyone know why the B21 only had 13 PTO horsepower?
When other 20 horsepower tractors are in the upper teensIs it the gearing or the extra weight?
I’d like to find a way to turn the power up just a couple horsepower-have a 3 point snowblower and it bogs in heavy snow. Lowest gear in the hydro.

does the B21 have different gearing than others?

Tractordata says pto has 13.5 hp.
If you compare machines with hydrostatic and manual transmissions you will see the HST robs the system of power.
Your B21 is a loader backhoe and I suspect it has a larger hydraulic system than a similar non loader backhoe model which also requires more engine power.

If the loader were removed during snow blowing it may free up a few HP but this is a guess and doubtful if you would notice the difference.
Dave

 

[mikester]

But does anyone know why the B21 only had 13 PTO horsepower?

It's a garden tractor, thats why

 

[GreensvilleJay]

curious, how wide a snowblower are you running ?

 

[hagrid]

It's a garden tractor, thats why

Lawn mower!

 

[TheOldHokie]

Tractordata says pto has 13.5 hp.
If you compare machines with hydrostatic and manual transmissions you will see the HST robs the system of power.
Your B21 is a loader backhoe and I suspect it has a larger hydraulic system than a similar non loader backhoe model which also requires more engine power.

If the loader were removed during snow blowing it may free up a few HP but this is a guess and doubtful if you would notice the difference.
Dave

Think about that. The only power loss is from the friction/resistance of the oil circulating through the neutral circuit in the valve. That is:

1. For all practicable purposes immeasurable
2. Does not go away or decrease when you dismount the loader.

Dan

 

[cthomas]

I disagree, if you remove the loader, the tractor has less weight to move, therefore, move power to the PTO. I do realize it's not a big gain(but every bit helps).

 

[TheOldHokie]

I disagree, if you remove the loader, the tractor has less weight to move, therefore, move power to the PTO. I do realize it's not a big gain(but every bit helps).

Perhaps you should re-read the comment to which I was responding and quoted. It was about hydraulic load not implement weight.

But since you brought it up I suspect that loss/gain is also close to immeasurable. And absolutely the case sitting hooked up to a dynamometer which is how these OEM horsepower numbers are actually measured

Dan

 

[Connor]

54” new holland-I had a same size Kubota blower but the new holland has heavier components. Makes it take a little more power to turn. But it does a nicer job blowing snow than the Kubota did.

And yea I get it a B21 isnt any more horsepower than my lawn mower.
but it makes a nice little loader around the house

curious, how wide a snowblower are you running ?

 

[cthomas]

I know I can feel a difference when mowing the lower field (tall grass-on a hill) between loader on and loader off. My LX2610 tractor weighs about 2500 pounds and the loader is another 500 pounds Therefore, when the loader is removed more power is available to the PTO as the HST using 20 percent less force to move just the tractor. Yes, some lawnmowers have higher horsepower, but, make less torque.

 

[Connor]

is there a way, to turn up the injection pumps on these just a little? Or bigger injector nozzles?
im not overly familiar with Kubota small engines

I know I can feel a difference when mowing the lower field (tall grass-on a hill) between loader on and loader off. My LX2610 tractor weighs about 2500 pounds and the loader is another 500 pounds Therefore, when the loader is removed more power is available to the PTO as the HST using 20 percent less force to move just the tractor. Yes, some lawnmowers have higher horsepower, but, make less torque.

 

[TheOldHokie]

I know I can feel a difference when mowing the lower field (tall grass-on a hill) between loader on and loader off. My LX2610 tractor weighs about 2500 pounds and the loader is another 500 pounds Therefore, when the loader is removed more power is available to the PTO as the HST using 20 percent less force to move just the tractor. Yes, some lawnmowers have higher horsepower, but, make less torque.

You are missing the entire point. Here is the original question which was why is the BX PTO horsepower less than other tractors with the same size engine.

But does anyone know why the B21 only had 13 PTO horsepower?
When other 20 horsepower tractors are in the upper teensIs it the gearing or the extra weight?

The answer to that question has NOTHING to do with the loader. PTO horsepower is measured on a stationary dynamometer and its relationship to engine horsepower is a function of the efficiency of PTO drive line.

Dan

 

[cthomas]

Yes, the injection pump does have a fuel screw(it is covered with a anti-tamper cap). I am familiar enough with diesel engines that before I would mess with it, I would borrow a PTO dyna(my old work place has one), install an EGT sensor to monitor exhaust temperatures, research the crap out of it. I have done different injectors in my cars(VW/Audi's TDI) and a thinner head gasket to increase compression(after measuring piston protrusion). Also I have done(in a previous lifetime) emissions deletes and reprogramming using EFI Live(2008 CCLB dually could spin all 4 back tires taking off((Me and late father playing around, tune in truck for about one hour)).
As for loader on or off, if the engine is dropping RPMS to climb a hill, the PTO HP is going to suffer. It is that simple, less weight of the tractor means the PTO is getting more of the engine HP. Now the B21 may have an more inefficient PTO setup as any hydrostatic tractor will have less PTO HP versus a gear drive.

 

[Connor]

You are missing the entire point. Here is the original question which was why is the BX PTO horsepower less than other tractors with the same size engine.


The answer to that question has NOTHING to do with the loader. PTO horsepower is measured on a stationary dynamometer and its relationship to engine horsepower is a function of the efficiency of PTO drive line.

Dan

I see, that second part makes more sense. So I’m thinking the PTO on this is probably the last piece in terms of priority on this tractor? With more of the driveline going to the other components.

 

[hagrid]

Add turbo.

 

[cthomas]

Supercharger, the power is a lot quicker. Or pull a Volvo and do both.....
The star of the show is the 2.0-liter inline 4-cylinder T6 engine, which combines turbocharging and supercharging with the goal of attaining the best of both possible worlds. Claiming to be the first in its class to deliver over 2 horsepower per gram of CO2 emissions, the T6 churns 302 horspower, 295 lb-ft of torque, a 0 to 60 mph time of 5.6 seconds, and a respectable fuel economy rating of 24 mpg city, 35 mpg highway. Got to drive one once, it was fun.

 

[lugbolt]

Those tractors use a open center hydraulic system.

In a nutshell, it was covered in that the hydraulic pump(s) (some TLB's have more than one), will have to move much more fluid. In an open center system, fluid is always being pumped through all of the valves. The more fluid that it pumped the more load there is on the pump, which robs power.

Dedicated TLB's are not really designed around the PTO, they were prioritized to use the Loader and Backhoe more than the PTO. That's the main reason, for the very short time I did sales, I opted to push folks away from the TLB if they were going to be using the PTO much, and if they just had to have it, always tried to advise them that the pto power would usually be down in comparison to a comparable non TLB tractor with the same engine horsepower.

 

[cthomas]

Ok, that sounds like the reason.

 

[mikester]

Lawn mower!

Garden tractor is the politically correct term for lawn mower...

 

[GreensvilleJay]

A 54" snowblower seems like a LOT of blower for 13-14HP to spin,especially anything 'kinda' wet.
Most walkbehinds in that HP class are30-35" augers,and use 1-2HP to move them.
I have to wonder what the MFR ( ?) of the 54" blower did that says 13Hp is 'OK' for it.

FWIW , in my area, a 'lawn mower' is designed to JUST cuts grass, a 'garden tractor' is sold with plow,tiller and forklift. My ancient Sears ST12(repowered DOWN to 9HP) pulls a Brinly 10" plow perfectly in the garden a 2 passes makes great mini ditches.