Can someone please explain the PTO differences in the L2800,3400,4400??

[Robert6401]

I am planning to buy one of these tractors, and their options on the PTO confuse me (sorry for my obvious lack of knowledge on the subject). There are 4 different PTO's in this lineup:

1) Transmission driven with overrunning clutch, on L2800DT

2) Live - continuous with overrunning clutch, on L2800 and L3400 HST

3) Live- continuous running, on L3400DT

4) and Hydraulic - live - independent, on L4400

Now, I think I understand the difference between option 1 and 4, but whats the difference between 2 and 3??? Thanks for the help.

Bob

 

[Crash101]

Robert 6401
2) Live - continuous with overrunning clutch, on L2800 and L3400 HST
3) Live- continuous running, on L3400DT

The difference here is the tractor's transmission itself. The gear driven tractor of course uses the clutch for the gears as normal and also for the PTO gear. The HST transmission ( a hydraulic pump) on the other hand uses no clutch in that it's one pedal to go forward, the other to go backward. Push more and go faster, let off and come to a stop. The PTO is still gear driven and not independant as it should be, so therefor it still needs a clutch, same as the PTO on the manual transmission tractors.

 

[Leon Wittner]

I have the L2800 with standard transmission and it does not have the double clutch. The PTO shaft does not turn until the clutch is released and the tractor is moving. The double clutch allows the PTO to start before the tractor clutch is completely released as my dealer explained it to me. I am sure there are some others on here that know a lot more about it than I do. My L2800 has FL loaded tires and is about 3 1/2 years old with 100 Hours on it. I could not be any happier with any tractor, I love my Kubota so much I just bought a new Kubota RTV900 Work Site Utility Vehicle (two hours of use so far).

 

[canoetrpr]

I'll add something to confuse you more.

Most recent (2006+) models of the L2800/L3400 HST DO NOT have an over running clutch even though Kubota hasn't updated the spec sheet The over running clutch used to be built into the PTO engagement cams in earlier models(as it is in mine). When the PTO was engaged and the clutch was depressed, the built in ORC would rachet not allowing the momentum of the implement to 'drive' the transmision.

Now the wierd thing about this is that no one seemed to be able to explain why a HST tractor which is clearly not going anywhere whent he HST pedal is not depressed needed a mechanism like an ORC to begin with. I can only assume that it was done to take the pressure off something in the main drive internally.... no real clue.

The PTO cam design was 'upgraded'. It is not absolutely clear why ... but it is thought to be because it led to premature failures in the PTO on some machines. That said, there was only one report on this site about one such failure. I'll bet Kubota also got a LOT of complaints about the racheting noise the ORC made when the clutch was depressed with PTO engaged.

All of this is water under the bridge, except for the fact that the L2800/L3400 sure does not have an ORC anymore... so it would not shock me if there is absolutely no difference between 2 and 3 anymore... which makes me further wonder - why did they think they needed a ORC there in the first place, if they just decided to go ahead and remove it

 

[canoetrpr]

Just re-read what Leon said. Unlike his description of the standard tractor, the PTO ont he HST will definately run even when the tractor is not moving, as soon as you take your foot off the clutch.

 

[Jeffrla]

Hello,

I am new here and I am looking buying a L-Series tractor. I grew on a farm in Texas and we had a JD 4010 with an independent PTO (Lever on side of dash). Pto was either on or off. Quite simple if you ask me. Then we had a JD "B"...It had a transmission Pto. Stop the tractor, engage the pto lever, engage the hand clutch, and the tractor and pto would start.

I believe I understand the premise of the overrunning clutch in that it does not allow torque to back flow to the transmission when the operator stops the tractors movement.

I have been looking at the Kubota L-Series and in particular I am looking at the gear drive tractors. I just cannot bring myself to buy a hydro at this time. I am considering the L2800 or the L3400 gear tractors, but I am confused by the wording on the Kubota site. It says the L2800 has a transmission driven pto w/overrunning clutch. The L3400 says it has a Live Continuous Running pto. It does not state that it has an overrunning clutch. The L3400HST says it has a Live Continuous Running PTO w/overrunning clutch.

Wouldn't it be a safety/mechanical issue to have the Live PTO w/o the Overrunning clutch?. If you stop the tractor, torque from say a rotary cutter could backflow and cause the tractor to roll forward.

Thanks in advance.

Jeff

 

[simonmeridew]

on my gear L4400, you can engage or disengage the pto at any time without any use of the clutch.There is no gear crunching at any time. the lever needs to be in the "off" position in order to start the engine however. I cannot speak to the overriding clutch issue as I only run a logging winch via the pto.
simonmeridew

 

[Chilly807]

Mine is a gear drive 3400. 2009 model. The two stage clutch works like this. With pedal fully depressed nothing runs, both the PTO output shaft and the drive wheels don't move. You can engage the PTO lever at this point, or select whichever gear you want for the tractor itself.

When you begin to let the clutch out, the PTO starts turning first, bringing the implement up to idle speed at least. Let the clutch out further and the wheel drive engages and begins moving the tractor. There's maybe an inch or so of "dead travel" between the time the PTO clutch engages and the time the wheels start to get power.

I thought the 2 stage clutch was a gimmick when I first got the tractor, but it makes sense. The larger implements take a bit of power to get spinning, then the wheels take a bit more, so it eases the initial load on the engine.

I've been really happy with the L3400 with the gear drive, it's the right tractor for me. I don't like the complexity of the HST, any vulnerability of a cooling fan to damage, and I don't know how well the HST will handle cold temperatures and thick oil over a number of years.

I will say one thing, anyone thinking of getting the gear drive had best drive one before they commit. The clutch is not brutally heavy, but you do need a decently strong left leg to be comfortable using it. The gear ratios are great, something for every occasion. I usually bush hog in 3 or 4 low in heavy stuff, and up to 2 high in easy going depending on how bumpy the ground is.

Low range works well with the loader, usually 3 low to dig, and 3 high to transport a full bucket.

Great machine, comfortable to run all day if you need to.

Chilly

 

[Jeffrla]

Hi all,

Chilly807...thank you for the emplanation. It makes things come into focus now.

Thanks,

Jeff