Kubota B2710 PTO setting for Wallenstein BX 52S chipper

[PETDOC]

My B2710 has 2 options for setting the power take off speed: "PTO" and "540". The manual for the chipper suggests adjusting throttle to about 90% of maximum. My assumption is with the PTO setting the speed of the PTO is directly related to the engine rpm, whereas in the 540 setting the rpm of the PTO is held at 540 and the throttle only controls the torque.
My question is do I select the PTO setting or the 540 setting? The B2710's PTO hp is near the minimum recommended for operation of the Wallenstein BX 52S, hence I purchased the model without the power feeder.

 

[ericm979]

The Wallenstein manual should say what it's input RPM is supposed to be... but 99% it's 540. Older Japanese tractors often came with a two speed PTO with 1000 rpm being the other speed, as that was common in Japan. You'll want the 540 setting. The tractor's manual should tell you how to set the engine to get the pto to turn at 540. If you have a tachometer it may have a mark for that engine rpm. The 540 setting on pto doesn't keep the engine rpms at the right speed. It's not that smart.

Adjustable power feed would have made the chipper work better for your minimal power tractor as you could slow the feed rate to match the tractor's power. It's also safer for the operator than the "chuck and duck" self feeding type.

 

[CobyRupert]

So you’re saying that with 540 setting, even if the tractor is at idle, the PTO is turning 540? I’m guessing 540 mode is for fuel (and noise) savings, so you can do light duty, low torque jobs at reduced engine rpms.
Seems like there’d have to be an electronic governor that increases engine fuel so it doesn’t stall if load increases? And how fast can it respond?
Instead of discussions about torque curves (and their sweet spots vs the engine rpm at 540 PTO rpm), governors, electronics, etc.., I’d use “regular” PTO mode.

 

[PETDOC]

My apology! There is only 1 setting on the lever for the rear PTO on my B2710 and it is for 540. The other mark on the lever guide merely identifies it as the rear PTO.
The owner's manual does specify an engine rpm for running the rear PTO and a different engine rpm for the belly PTO.

 

[CobyRupert]

Ha, ha, no problem. If you didn’t break it, throw money at it, or hurt yourself with it: IT’S ALL GOOD!

 

[check]

So, for my Kubota BX 25, is the rear PTO always running at 5:40, or only if I am at full throttle?

 

[ericm979]

Only if you're at the engine rpm that makes the PTO turn 540 rpm. That's usually a little less than maximum rpm from full "throttle".
The tractor owner's manual will tell you what that engine rpm is. Sometimes there's a mark on the tach.

The PTO is directly driven by the engine (after the clutch) through a set of reduction gears. Its rpm is a direct function of the engine rpm. If the engine's PTO rpm is 2500, running the engine at 1250 will result in the pto turning 540/2 or 270.

 

[check]

Only if you're at the engine rpm that makes the PTO turn 540 rpm. That's usually a little less than maximum rpm from full "throttle".
The tractor owner's manual will tell you what that engine rpm is. Sometimes there's a mark on the tach.

The PTO is directly driven by the engine (after the clutch) through a set of reduction gears. Its rpm is a direct function of the engine rpm. If the engine's PTO rpm is 2500, running the engine at 1250 will result in the pto turning 540/2 or 270.

Kk thanks, Eric. Will dig up my manual and see what it says.

 

[zzvyb6]

So, for my Kubota BX 25, is the rear PTO always running at 5:40, or only if I am at full throttle?

Pour me another. It's 5:40 somewhere.

 

[blacklion66]

your manual will tell you what RPM you need to have the PTO at 540// forget all that crap ,if your chipper is rated for a 4 inch limb try a 3 inch, if it dogs the motor down increase the engine RPM

Sometimes manuals just make thing more complicated than they have to be☺
as your chipper blades get dull you are going to have to give it more go juice☺
After you stall the engine once or twice it all becomes natural to where you set the hand throttle

A well made chipper with a power feed is the only way to go, helps keep fingers out of the chipper!