Powershift Transmission...

[jlinn1]

I was just searching for alittle history to be more familiar with my Yanmar, and was curious....... I know yanmar built John Deere's compacts up until 86' or so and still provides engines for some of their compacts. Did Yanmar also share their powershift transmission with John Deere for compact tractors or is this an exclusive to Yanmar?? All Ive ever found on this subject, is that tractors are pretty much either manual shifts or Hydrostatic these days....

My powershift 1610D is so handy for normal use that I cant believe other brands wouldnt be using it. Does anyone have more insight on this topic or know more history surrounding Yanmar and John Deere's relationship with compact tractors??

Justin

 

[soulasphil]

Is the Power-reverser transmission to be found on the JD 3520 or 4520 what you mean ? It allows you to drive forward or backward at the same speed at the flip of a small lever. I love it, especially for loader work.

 

[drippingwithgold]

Is the Power-reverser transmission to be found on the JD 3520 or 4520 what you mean ? It allows you to drive forward or backward at the same speed at the flip of a small lever. I love it, especially for loader work.

No, totally different subject.

 

[Gary Fowler]

Check out the Massey Ferguson new QPS (quadra power shift). This appears to be similar to theYanmar powershift. One poster here said that the MF dealer said that they were having some early problems with it though. It looks to be a powershift similar to Yanmar in that you can powershift 4 gears without clutching in each of 3 ranges. You have to stop and shift ranges just like Yanmar. THe difference is that in each powershift gear, you also have a reverse so you have 12 forward and 12 reverse unlike my Yanmar that has 12 forward and 4 reverse (4 gears and 3 powershift and reverse-Neutral in each) MF looks to have tried to improve on a proven technology but didnt get i quite right. Lots of electronic on theirs rather than a linkage like Yanmar.

 

[Gary Fowler]

QPS only available on there 45 and above hp models and only those with a cab. Must be something about the electronic shifting that has to be protected from the weather.

 

[Smoody]

I don't think any manufacturer will be able to duplicate the Yanmar design, its as close to perfect as you will get. I just got a Yanmar with powershift and don't think it could get any better. I did not have to settle on a grey market tractor because of budget, I had the $$ saved to buy about any brand I wanted, I still chose the Yanmars, can't beat the quality of the tractor at the price. So instead of getting 1, I ended up with 2 tractors and use both daily.

 

[jlinn1]

Ive caught quite a bit of laughs from a friend who runs a New Holland compact for his landscaping business, until he woke up one morning and had a flat rear tire. So I offered to let him use my Yanmar for the day until he could get it fixed and he was very impressed with it after running it. To hear that from a "Die Hard" New Holland fan it was a pretty good ego boost for me!!

This was basically my purpose for this thread about the powershift transmission, thats the part he was most impressed with compared to the "hydros" that he has ran in the past. Maybe if a stay on him about it, I can convert him to Yanmar man!!

 

[soulasphil]

No, totally different subject.

So what does the Yanmar powershift do ? just change gears without clutching ?

 

[California]

So what does the Yanmar powershift do ? just change gears without clutching ?

There are clutches and gears inside similar to an automatic transmission except there is no torque converter.

The Powershift shift lever is linked to valves that send hydraulic fluid into the clutches that engage one of its speeds - three forward, one reverse.

After one of the Powershift clutches is engaged there is a straight mechanical connection through the transmission. And there is nothing to make it upshift automatically, instead you move the shifter to the next position.

The powershift portion is 'behind' a conventional 3 range transmission and ordinary clutch. So you select a gear range, let out the clutch, then shift the Powershift shifter from its neutral to reverse, first, etc to start moving. There is a slight delay (restriction) built into the Powershift fluid circuits to make the shifts gentle.

The powershift allows no-clutch full power upshifts and downshifts while moving so you don't lose inertia. They probably didn't intend that on hard pavement, but remember these were designed with slippery rice paddies in mind.

And the PTO is driven from the 'front', conventional transmission so it turns as long as the clutch is engaged. You can shift the Powershift to its neutral and come to a stop with a mower etc engaged.

(Front and Rear are just to make this description clear. Actually both transmissions are in one case).

 

[irwin]

There are clutches and gears inside similar to an automatic transmission except there is no torque converter.

The Powershift shift lever is linked to valves that send hydraulic fluid into the clutches that engage one of its speeds - three forward, or reverse.

After one of the Powershift clutches is engaged there is a straight mechanical connection through the transmission. And there is nothing to make it upshift automatically, instead you move the shifter to the next position.

The powershift portion is 'behind' a conventional 3 range transmission and ordinary clutch. So you select a gear range, let out the clutch, then shift the Powershift shifter from its neutral to reverse, first, etc to start moving. There is a slight delay (restriction) built into the Powershift fluid circuits to make the shifts gentle.

The powershift allows no-clutch full power upshifts and downshifts while moving so you don't lose inertia. They probably didn't intend that on hard pavement, but remember these were designed with slippery rice paddies in mind.

And the PTO is driven from the 'front', conventional transmission so it turns as long as the clutch is engaged. You can shift the Powershift to its neutral and come to a stop with a mower etc engaged.

(Front and Rear are just to make this description clear. Actually both transmissions are in one case).

That sounds similar to the Glide shift trans on my Kubota L35TLB.