General Yanmar PTO Question

[driver444]

I'm just asking for a buddy of mine. On all these "gray market" Yanmars, are they transmission driven PTO's, or on dual stage clutches? He's specifically interested in the YM series, not sure which model yet. (1610D maybe?)
Thanks

 

[chriswheeler]

I don't know what all of the YM series does, but I do know that my YM 3000 has a single stage clutch and so does the 2500. My John Deer 950 that could have come off the same production line has a dual clutch, rear disc for PTO, front disc is for the drive. The dual clutch is much more of a pain to adjust.
Chris

 

[driver444]

That's what I thought. So the smaller Yanmars are NON-live PTOs. Thanks for the reply

 

[Coyote]

I think they are dual stage clutches...there are seperate clutches to engage the transmission or just the PTO

 

[tallyho8]

My YM1802 has a single stage clutch.

 

[Tom_Veatch]

My 2220D does not have a live PTO.

The clutch disconnects the engine from the transmission, but does not disconnect the PTO and the transmission. If the PTO lever is not in its neutral position, when the transmission turns, so does the PTO and vice versa. An over-running clutch attachment on the PTO output shaft is highly recommended for any attachment with a significant rotary inertia, i.e. a rotary cutter.

 

[lens12]

All the YM series are single stage clutches. The powershift models can be operated like a live pto by not using the clutch when shifting transmission gears.

 

[Acre Garden]

Wow!!! I wish I was smart enough to know what you guys are talking about. Sound interesting.

 

[kenmac]

I had a to-20 onc that operated the same way. single stage clutch. Push clutch in PTO stops.

 

[California]

Wow!!! I wish I was smart enough to know what you guys are talking about. Sound interesting.

Simpler than it sounds. The pto-out shaft is connected directly to the internal transmission gears when you shift the pto lever from Neutral to 540. So when the clutch is engaged, the pto turns. Clutch in, it stops.

However - whenever the gears are turning, either because the tractor is coasting or a because a big rotary mower is spinning down, everything is still connected. Even if you push the clutch pedal in, the rotary mower has so much inertia it can push you into tearing the corner off your house. (vivid metaphor so it's easy to remember!) That's why everyone recommends adding an overrun clutch (like a bicycle coasting mechanism) to the models that don't already have it.