E-PTO and constant RPM mgmt for Kubota M series

[tlj87]

In shopping for a Kubota tractor (considering L5460, MX5400 and M5660SUHD), e-PTO is an option for the M5660. My most demanding PTO application at this time is powering a Woods RD990X 90" finishing mower. If buying new, would the $1000 e-PTO option be worth it? Literature states "Simply select ?40E and the PTO shaft rotation speed is maintained at 540 rpm while the engine speed runs at 1828 rpm with limitation to 2132 rpm, thereby reducing both operating noise and fuel consumption." Does it have any affect on the operation of the machine for non-PTO work? Is there any concern about lower RPM operation during e-PTO use and the emissions system?

A second question, independent of E-PTO, is the constant RPM management feature (standard) basically the same as "Stall Guard" on the Grand L series? I can't see why one would ever turn this feature off (there is a button to toggle it on/off)?

 

[MessickFarmEqu]

E-PTO is kinda a silly feature. The idea was to save fuel, but a modern electronically controlled engine burns based on torque load.. and that does not change @ 540E.

Agree with you that I don't know why you would turn off constant RPM.

 

[Jchonline]

It might save a bit of fuel, but if you are buying a modern machine they like to be at PTO engine RPM anyway for particulate burnoff. I do not think it is worth it. Not sure about the constant RPM feature. My father has a M7060 and I dont recall reviewing it with him.

 

[ericm979]

E-PTO is kinda a silly feature. The idea was to save fuel, but a modern electronically controlled engine burns based on torque load.. and that does not change @ 540E.

Doesn't even an old mechanical injected tractor fuel the engine based on torque load? Both are keeping the engine running at the rpm the operator set, using an electronic or a mechanical governor.

The fuel savings from E-pto would be from the difference in internal engine friction and pumping losses, and external engine accessory power consumption (i.e. hydraulic pumps) between the lower and higher rpms. Which is something, but not a lot. It'll also be somewhat quieter.

I have E-pto on my Tier 4 but mechanically injected Branson, and I never use it. Most of my PTO operations can need full power at times. Also Branson wants you to run the engine between 2000 and 2500 for best emissions system performance, and the E-pto engine speed is 1850 rpm.

 

[Sawyer Rob]

Providing you aren't "over loading" the engine using the E pto setting, you will save fuel, but it would take a LONG time to save 1k back in fuel cost.

SR

 

[ptsg]

I use 540E on my tractor all the time. Either mowing heavy brush or using the tiller, I always use 540E.

I can do the same job using 540E instead of the regular 540, plus it will burn less fuel, makes less noise and with gear tractors, will give you even more options by playing with ground speed and 540 or 540E PTO.

I don't have emissions on my tractor, but on tractors with emissions, it may or may not create an issue. If you have enough load on the PTO with the 540E engage, I don't think it'll be a problem.

But the best thing with having more than one PTO speed is that you'll have a lever to switch between 540 - Neutral - 540E or other speed. This, in my opinion, is essential on tractors with a clutch pack for the PTO engagement. On these tractors, with the PTO in the Off position, the PTO will have a spring actuated brake preventing it from rotating, thus making connecting the PTO shaft from implements an absolute pain since you can't rotate the shaft.

Once you put the PTO lever to Neutral, you can rotate easily. It make life a lot easier.

 

[ericm979]

I agree, being able to put the PTO in neutral is useful for attaching implements.

 

[nards444]

Might make sense if you had long constant work, as in mowing acres and acres of grass where you knew the RPM had to be. I can see the upside on it. Just not sure if it work for everybody