Jump to content

Nominations for Tractor of the Month
Garden Tractors and Parts on eBay



Photo
- - - - -

Can A 2Wd Gt Be Converted To Hydro 4Wd?

4wd hydrostatic hydrostatic motor hydrostatic 4wd 4wd conversion

  • Please log in to reply
26 replies to this topic

#16 superiorpower OFFLINE  

superiorpower

    New Member

  • Member
  • Member No: 3881
  • 41 Thanks
  • 67 posts
  • Location: Central Missouri

Posted March 04, 2014 - 12:23 AM

I have always considered building my own machine from scratch just because I figured I could never afford a good 4x4 tractor. My plan would have been to use a hydro pump and wheel motors. I considered installing a wheel motor to a front and rear differential but wondered how that would affect turning since the front wheels would be making a smaller radius than the rear wheels. But I guess all 4x4s are that way, including trucks... I love dreaming. And Dreaming. And dreaming. And dreeeeeeeeeaaaaming....  :wave:


  • Utah Smitty said thank you

#17 skyrydr2 ONLINE  

skyrydr2

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 5032
  • 3,404 Thanks
  • 3,155 posts
  • Location: Gardner, Massachusetts!

Posted March 04, 2014 - 04:06 AM

That is pretty much how all the newer GTs do it like Simplicity and John Deere on their 700 series. Its easy and effective for them... They pay big dollars to engineers to come up with that kind of stuff ;-)

#18 Alc ONLINE  

Alc

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 1094
  • 5,445 Thanks
  • 6,611 posts
  • Location: Bangor Pa

Posted March 04, 2014 - 06:38 AM

We had a training course at work and they got us a book from Parker called Mobile Hydraulic Technology Bullentin 0274-B1 which has some great info on the subject , if you can find/borrow one it might give you some good ideas , cost new is $99

 

http://parker.com/po...M10000048021dac____



#19 JDBrian OFFLINE  

JDBrian

    Super Moderator

  • Super Moderator
  • Staff
  • -GTt Supporter-
  • Contributor
  • Member No: 2507
  • 9,574 Thanks
  • 14,136 posts
  • Location: Hubley, Nova Scotia - Canada

Posted March 04, 2014 - 06:41 AM

The single motor driving the front dif would be a valid way to go. You need to match the speed to the rear wheel speed which you would do by regulating flow or limiting pressure to a low level which would limit the torque available. On my 2320 it's a mechanical 4wd but it's driven off the transmission and I've noticed that the front drive wheel will spin fast if it looses traction, which tells me there is a hydraulic component in the drive that allows higher speed to the wheel when there is no load. With a strictly mechanical system the wheel speed would stay the same when it lost traction. I've never really taken a close look at the service manual to see how it works. 


  • Alc and Utah Smitty have said thanks

#20 Utah Smitty OFFLINE  

Utah Smitty

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 5557
  • 1,643 Thanks
  • 1,746 posts
  • Location: Northern Utah

Posted March 04, 2014 - 04:21 PM

The single motor driving the front dif would be a valid way to go. You need to match the speed to the rear wheel speed which you would do by regulating flow or limiting pressure to a low level which would limit the torque available. On my 2320 it's a mechanical 4wd but it's driven off the transmission and I've noticed that the front drive wheel will spin fast if it looses traction, which tells me there is a hydraulic component in the drive that allows higher speed to the wheel when there is no load. With a strictly mechanical system the wheel speed would stay the same when it lost traction. I've never really taken a close look at the service manual to see how it works. 

That's along the lines of what I had in mind... just not sure how to regulate flow to the motor. You'd want something that would increase flow as the tractor speed increased, etc.... 

 

Maybe OCH is right... it's too complicated and my mind just get's all tangled up trying to think about it!!

 

Smitty



#21 TAHOE OFFLINE  

TAHOE
  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 24522
  • 6,480 Thanks
  • 4,937 posts
  • Location: "Hamiltucky" Ohio

Posted March 04, 2014 - 08:29 PM

It ended up not being a Hydro rear, but both are geared but here is video anyway

His channel has like 12 videos or so on the build.

 

http://www.youtube.c...ure=c4-overview



#22 coldone OFFLINE  

coldone

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 839
  • 1,631 Thanks
  • 1,668 posts
  • Location: Central NC

Posted March 04, 2014 - 10:34 PM

How about a cut down auto rear end driven by Hydro motors. Much like a Case hydraulic drive setup but using a hydrostatic variable displacement pump. The pump would drive the hydro motors. One hydro motor would be the input for the rear axle and the other motor would be the input for the front axle. The front axle would be a cut down 4X4 axle. If the final gears in the front and rear axels are the same then you wouldnt have to deal with reductions of the hydro motors.

 

Hydro pump

http://www.surplusce...09-9-8238-R.axd

 

Hydro motor

http://www.surplusce...C-9-7073-75.axd


  • Utah Smitty said thank you

#23 Utah Smitty OFFLINE  

Utah Smitty

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 5557
  • 1,643 Thanks
  • 1,746 posts
  • Location: Northern Utah

Posted March 05, 2014 - 12:13 AM

How about a cut down auto rear end driven by Hydro motors. Much like a Case hydraulic drive setup but using a hydrostatic variable displacement pump. The pump would drive the hydro motors. One hydro motor would be the input for the rear axle and the other motor would be the input for the front axle. The front axle would be a cut down 4X4 axle. If the final gears in the front and rear axels are the same then you wouldnt have to deal with reductions of the hydro motors.

 

Hydro pump

http://www.surplusce...09-9-8238-R.axd

 

Hydro motor

http://www.surplusce...C-9-7073-75.axd

That would work if I'm building from scratch... What I wanted to do was to put a steering live axle under my Bolens HT23 since I can't afford a CUT right now...

 

Thanks for the suggestion.. the prices for the components from Surplus Center are pretty good.

 

Smitty



#24 skyrydr2 ONLINE  

skyrydr2

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 5032
  • 3,404 Thanks
  • 3,155 posts
  • Location: Gardner, Massachusetts!

Posted March 05, 2014 - 04:11 AM

Brian your 2320 is totally mechanical, what you saw was the results of the diffential .

Smitty, you need to find a small enough axle that would fit under your machine first, then you can do the math to figure out what you needto drive it.
Tuff torque makes everything you are looking for. The hydro that drives it all the way up to the front diff . Go look at a new Deere X 700 and see how they did it, soooo simple yet effective!!
  • JDBrian and Utah Smitty have said thanks

#25 JDBrian OFFLINE  

JDBrian

    Super Moderator

  • Super Moderator
  • Staff
  • -GTt Supporter-
  • Contributor
  • Member No: 2507
  • 9,574 Thanks
  • 14,136 posts
  • Location: Hubley, Nova Scotia - Canada

Posted March 05, 2014 - 06:01 AM

Brian your 2320 is totally mechanical, what you saw was the results of the diffential .

Smitty, you need to find a small enough axle that would fit under your machine first, then you can do the math to figure out what you needto drive it.
Tuff torque makes everything you are looking for. The hydro that drives it all the way up to the front diff . Go look at a new Deere X 700 and see how they did it, soooo simple yet effective!!

Thanks Keith. After I wrote it I got to wondering if that was the case. It would be twice as fast with the undriven wheel not moving which is usually the case when you are pushing snow into a pile. I think the fronts are usually slightly overdriven (slightly faster than the rears) in these setups aren't they.

  Those 700's with the hydraulic front drive really work well. If the wheels are straight both fronts will pull which is generally going to be better than with a conventional open front dif. Kubota also has a similar system on their GR series GT's.


  • Alc and skyrydr2 have said thanks

#26 JDBrian OFFLINE  

JDBrian

    Super Moderator

  • Super Moderator
  • Staff
  • -GTt Supporter-
  • Contributor
  • Member No: 2507
  • 9,574 Thanks
  • 14,136 posts
  • Location: Hubley, Nova Scotia - Canada

Posted March 05, 2014 - 06:10 AM

Smitty, I have 4wd available on my 2320 but I don't use it that much. I have found that a set of chains and some weight on the back end is a better traction aid than 4wd or a dif lock. 4wd can be a help in deep sand or to help you steer but for most loader work and plowing I don't use it. If it proves too difficult or expensive to put 4wd on the HT23 you still have a very capable tractor that will do 90% of the work it would do with 4wd. Wheel weight, a ballast box and a set of 2 link or 2 link ice type chains would make that HT pretty unstoppable in most applications. As long as the loader is properly sized for the tractor you will not have a lot of trouble with traction if you have it setup with good tires, weight and when required, chains.


  • Alc and Utah Smitty have said thanks

#27 Utah Smitty OFFLINE  

Utah Smitty

    Tractorholic

  • Senior Member
  • -GTt Supporter-
  • Contributor
  • Member No: 5557
  • 1,643 Thanks
  • 1,746 posts
  • Location: Northern Utah

Posted March 05, 2014 - 10:01 AM

Brian your 2320 is totally mechanical, what you saw was the results of the diffential .

Smitty, you need to find a small enough axle that would fit under your machine first, then you can do the math to figure out what you needto drive it.
Tuff torque makes everything you are looking for. The hydro that drives it all the way up to the front diff . Go look at a new Deere X 700 and see how they did it, soooo simple yet effective!!

A 4wd steering axle off a Toro 322 mower is about the right size--tires are 8.50-18x8 and 40" to center of wheels.  It's a mechanical 4wd that is full time.  It has a roller clutch in the driveline. The rear axle runs a little faster than the front so the 4wd is only engaged if the front starts to slip and slow down...

 

Problem is there is no way to mechanicall run a drive line from the rear differential and I can't run a drive line off the engine drive shaft as it's turning too fast... haven't figured a way to synchronize the speed between the rear axles and the front. Plus the rear differential has two ranges which further complicates things.

 

I probably would have to pull out the HT 23s hydro and rear end and put the running gear from a SCUT under it, which defeats the purpose.

 

On the other hand, I ran across a series of threads where a guy mounted a loader on a Toro mower with rear wheel steer.  He had to lengthen the arms, but it worked out very well.  Since the biggest reason for having the 4 wheel drive and power steering is for easy maneuvering with the loader, this may be a good option if I can only find a 4wd mower at a good price and then pick up a loader reasonable... we'll see.

 

Thanks for your input, as always, it is thought-provoking...

 

Smitty







Also tagged with one or more of these keywords: 4wd, hydrostatic, hydrostatic motor, hydrostatic 4wd, 4wd conversion

Top