Using max pto HP?

[IndyIan]

I got into running a buddies 4x5 round baler this summer and needless to say, it gave my tractor a good workout. It was fun making 4x4's but much bigger I was running out of hp to actually move the tractor. The temp gauge really didn't move above normal but it sure was removing some heat.
Can a tractor make say 90-95% of rated power all day without a problem? I think the DK50 has the same cooling system so I figured I had a bit of a buffer.
It is too bad you can't see what the injector pump is actually doing although with the HST you can give the pedal a pump and either it will speed up or bog if the baler is using all the hp.
I just stayed in low range and 3.5 mph wasn't too bad as the fields are a bit rough.

 

[jenkinsph]

You can run at high loads all day but it is important to keep track of fluids and temperatures. Keep the radiator clean and check the air filter often if dusty or grass chaff is an issue.

 

[Sawyer Rob]

Problem is, your exhaust temp can go too high LONG before it shows up in your cooling system...

You should NOT pull more than 80% of the MAX, your PTO puts out, for extended periods of time...

I could "melt" my 5.9 Cummins right down, and never see the coolant over heat!!

SR

 

[MHarryE]

My Kubota M135GX displays %power as one possible selection. I typically run in the 90 - 100% range for hours at a time. I have the radiator, air-to-air after cooler, fuel cooler, hydraulic oil cooler, and air conditioner condenser to pull air through. If I don't keep them extremely clean I will get an ATAAC alarm after 10+ minutes running over 95% on a 80 degree or hotter day. I think the cooling system should have more margin but there is a lot of cooling load on a system and I'll drop a gear before I give up my air conditioner.our JD 7720 can never be loaded enough to budge the heat gauges. The larger tractors are built with more cushion. There is room for increased cooling capability.

 

[PoorPlowboy]

Problem is, your exhaust temp can go too high LONG before it shows up in your cooling system...

You should NOT pull more than 80% of the MAX, your PTO puts out, for extended periods of time...

I could "melt" my 5.9 Cummins right down, and never see the coolant over heat!!

SR

A Cummins 5.9 in an automobile is not designed for 100% duty cycle like an industrial engine in a tractor. A Cummins 5.9 is turned up to around 55hp per liter displacement. A DK40SE is 20.5hp per liter. That difference in tuning is what allows full duty cycle operation.

 

[brown40]

I believe they are designed to be able to run the PTO full on all day, provided air flow/heat transfer stays good--otherwise they'd have duty cycles or warnings in the manual about running them "greater than 'x' hours" before letting them cool. That does sound like a bigger job for your machine than it may have been designed for though. I think sizing implements to not take every scrap is part of the equation. A generator application would be a tall order on a duty cycle.

 

[ddbackhoe]

I got into running a buddies 4x5 round baler this summer and needless to say, it gave my tractor a good workout. It was fun making 4x4's but much bigger I was running out of hp to actually move the tractor. The temp gauge really didn't move above normal but it sure was removing some heat.
Can a tractor make say 90-95% of rated power all day without a problem? I think the DK50 has the same cooling system so I figured I had a bit of a buffer.
It is too bad you can't see what the injector pump is actually doing although with the HST you can give the pedal a pump and either it will speed up or bog if the baler is using all the hp.
I just stayed in low range and 3.5 mph wasn't too bad as the fields are a bit rough.

The baler probably requires more hp than you have to offer. Most balers in that size range require 40 pto hp to operate efficiently, so with only 32 pto hp available.........To answer the question though, running it for 8 hours at 2600 rpm should not be a problem.

 

[moriboy]

Agree with others, equipment is designed to run at 100% duty cycle for extended periods.

 

[CobyRupert]

HP is not a measure of force, torque or energy, it's a measure of the RATE of force or energy. The HP requirement of the baler is a function of the RATE of hay being fed into it, which is a function of windrow density and ground speed. (i.e. 1/2 the horsepower can do the same work in twice the time)
Sounds like the Kioti is actually be sort of self regulating if ground speed slows down when baler torque demand goes up.

 

[Sawyer Rob]

A Cummins 5.9 in an automobile is not designed for 100% duty cycle like an industrial engine in a tractor. A Cummins 5.9 is turned up to around 55hp per liter displacement. A DK40SE is 20.5hp per liter. That difference in tuning is what allows full duty cycle operation.

A 5.9 is an auto engine?? Then why is it in thousands of tractors, dozers and all kinds of other equipment that require extreme service?? Are you trying to say your Kioti is more HD than a 5.9??

Did you know that some 5.9's are only rated at a little over 100hp???

No matter, that was just an example... lol

The 80% rule was clearly printed in the manual of some of the new tractors I've bought, including two AGCO farm tractors. (NOT Cummins powered)

One of the Kubota's I use to own, I ran near MAX for several hours and although the coolant never over heated, it burnt the valve guides...

Run them to max boys, it's your money and they make more!

SR

 

[ddbackhoe]

HP is not a measure of force, torque or energy, it's a measure of the RATE of force or energy. The HP requirement of the baler is a function of the RATE of hay being fed into it, which is a function of windrow density and ground speed. (i.e. 1/2 the horsepower can do the same work in twice the time)
Sounds like the Kioti is actually be sort of self regulating if ground speed slows down when baler torque demand goes up.

Hmmm, so from your statement, if we use the rule of (torque x rpm)/5252 = hp..Why won't we come to the conclusion that the baler is requiring more hp than the tractor can provide thus slowing the forward movement of the tractor?

 

[meos1]

HP is not a measure of force, torque or energy, it's a measure of the RATE of force or energy. The HP requirement of the baler is a function of the RATE of hay being fed into it, which is a function of windrow density and ground speed. (i.e. 1/2 the horsepower can do the same work in twice the time)
Sounds like the Kioti is actually be sort of self regulating if ground speed slows down when baler torque demand goes up.

More precisely it is a measure of power where one HP is equal to 0.74569987 kilowatts or 745.7 Watts. The physical definition is one metric horsepower is needed to lift 75 kilograms (avg. body weight of a person) by 1 meter (3.28 feet) in 1 second. James Watt is credited with developing these definitions. Back to you CobyRupert....

 

[CobyRupert]

Hmmm, so from your statement, if we use the rule of (torque x rpm)/5252 = hp..Why won't we come to the conclusion that the baler is requiring more hp than the tractor can provide thus slowing the forward movement of the tractor?

Yes, we can come to that conclusion . ....and when it forward speed slows, baler requires less horsepower. Viola! Sounds like it's sort of self regulating (if forward speed is slowing faster than pto power is dipping).

More precisely it is a measure of power where one HP is equal to 0.74569987 kilowatts or 745.7 Watts. The physical definition is one metric horsepower is needed to lift 75 kilograms (avg. body weight of a person) by 1 meter (3.28 feet) in 1 second. James Watt is credited with developing these definitions. Back to you CobyRupert....

James What? He plays second base. Who?-"First base!"
My point being: horsepower is a measure of Power. Power is the rate of doing work. It is equivalent to an amount of energy consumed (or delivered) per unit time.
Think of it as this: a certain "task" (say driving your truck to the top of a hill) takes a certain amount of "Energy" or "Work". Regardless of how long it takes. Doesn't matter if you have a 500 hp motor and can drive in top gear and climb the hill in 10 seconds, you need to produce the same "energy" and perform the same "work" as if you had a 5 hp go-cart engine in your truck and used super low-range to climb the hill in 16-2/3 minutes. Both engines did the same work, and delivered the same energy. But "Power" is the ability for the 500 hp to deliver that energy in 10 seconds. i.e. how fast do you want to accomplish that work?

 

[gladehound]

Problem is, your exhaust temp can go too high LONG before it shows up in your cooling system...

You should NOT pull more than 80% of the MAX, your PTO puts out, for extended periods of time...

I could "melt" my 5.9 Cummins right down, and never see the coolant over heat!!

SR

For clarity - what is the hp rating on this cummins 5.9 that you could melt down? My stock 7.3 (235hp) would not get over 1000F inside the exhaust manifold under sustained WOT. And that was at 32 hp per liter. The kioti is only 20 hp per liter!

 

[andy1981]

A 5.9 in a dodge is rated for a lower duty cycle than it would be in dozer or tractor that's why a tractor or dozer has lower hp than the truck . You will see higher hp in marine engine from a 5.9 because they use water cooled turbos and and have bigger cooling sysytems

 

[IndyIan]

A 5.9 is an auto engine?? Then why is it in thousands of tractors, dozers and all kinds of other equipment that require extreme service?? Are you trying to say your Kioti is more HD than a 5.9??

Did you know that some 5.9's are only rated at a little over 100hp???

No matter, that was just an example... lol

The 80% rule was clearly printed in the manual of some of the new tractors I've bought, including two AGCO farm tractors. (NOT Cummins powered)

One of the Kubota's I use to own, I ran near MAX for several hours and although the coolant never over heated, it burnt the valve guides...

Run them to max boys, it's your money and they make more!

SR

Well that's the kind of experience I want to avoid. I can't find anything in owners or service manual about duty cycle but probably 80% is a good target with the odd 100% situation. I'll try to stick to mowing and raking next year although it was fun making bales.

 

[ddbackhoe]

....and when it forward speed slows, baler requires less horsepower. Viola! Sounds like it's sort of self regulating (if forward speed is slowing faster than pto power is dipping).

Umm, no. The attachment is requiring more power(torque, hp, work effort, force, rate, etc.), hence the tractor becoming slower.

 

[ddbackhoe]

Well that's the kind of experience I want to avoid. I can't find anything in owners or service manual about duty cycle but probably 80% is a good target with the odd 100% situation. I'll try to stick to mowing and raking next year although it was fun making bales.

Depends on which numbers you are using. if 100% is 3000 rpms, then 80% is 2400 rpm (pto speed). There should be something in your owners manual about operating pto powered equipment at x rpm (pto speed).

Borrowed from a JD 5205 manual:
Operating Tractor PTO

NOTE: Engine will not start if PTO clutch lever is engaged.

1. Depress clutch pedal, start engine and push hand throttle lever (A) forward until engine speed is sufficient to start PTO implement. Engine speed must be less than 2200 rpm.

2. Move control lever (A) forward to engage PTO. PTO indicator (B) will light when PTO is engaged.

IMPORTANT: A warning alarm will sound for a few seconds if you leave seat with PTO engaged.

3. Increase engine speed to rated PTO speed of 2200 rpm for 540 operation (C).

CAUTION: Turn key OFF to stop engine, set brakes and make sure all mechanisms have stopped before cleaning out machine or making any adjustments to PTO driven implement.

4. Pull control lever back to disengage PTO.

A-PTO Control Lever
B-PTO Indicator
C-PTO (540) Rated Speed

 

[brown40]

There are gensets that never stop running, usually set up in tandem or higher, that are only halted to change the oil and do PM in remote areas and jobsites. They are usually diesels, and usually could put out far greater hp & torque than they are configured for. The application the motor is put to, and the amount of fuel they are combusting makes a tremendous difference in durability/heat damage. An engine burning fuel to hit 150 hp is not going to generate near the heat of the same one tuned to make 450hp. Automakers hate tuners, because they change the specs from what the design team had in mind for the application. Tractor design teams have a goal in mind when they select and set up their powertrain, and that's to run all day within their rated specs, regardless of the application. Get beyond their intention, and...

 

[Jerry/MT]

I got into running a buddies 4x5 round baler this summer and needless to say, it gave my tractor a good workout. It was fun making 4x4's but much bigger I was running out of hp to actually move the tractor. The temp gauge really didn't move above normal but it sure was removing some heat.
Can a tractor make say 90-95% of rated power all day without a problem? I think the DK50 has the same cooling system so I figured I had a bit of a buffer.
It is too bad you can't see what the injector pump is actually doing although with the HST you can give the pedal a pump and either it will speed up or bog if the baler is using all the hp.
I just stayed in low range and 3.5 mph wasn't too bad as the fields are a bit rough.

How do you know you were running at max power? Remember that max rpm is not necessarily "max power output".