Hydrostatic Trannys

[Anonymous Poster]

Thanks to Gordon's post to check out

http://www.adtdl.army.mil/cgi-bin/atdl.dll/fm/5-499/toc.htm

I have finally figured out how Hydrostatic Drive Kubotas work.

But now I have a question.

Does it hurt for them to sit and idle for long periods with the same fluid in the pump when it is at zero displacement?

Do they instead bleed some fluid off so a fresh supply of cool oil is always flowing through the pump even at zero displacement?

Enquiring minds want to know and they also want a hydrostatic drive Kubota!

(this question moved from the Newbie/Hydraulics thread so it will get more attention.)

 

[MChalkley]

The fluid sitting in the pump (or motor, for that matter) isn't doing any work, so there won't be any heat generated in the oil, so it should be fine. The piston sliders are being lubricated, so they're ok. I can't see where there could be a problem.

MarkC

 

[Anonymous Poster]

I figured somebody would have real world experience on this point and since Mark says it's OK I am sure it is. By the way Mark, what percentage would you say you utilize your horsepower, traction etc? You don't ever break your Kubota but you have bigger tires and more traction and a bigger bucket etc... It seems to me that if anyone could find a weak point it would be you, and I can't remember you ever having any trouble with yours, on top of you working it to it's extreme every day.

 

[MChalkley]

Kubotadriver (Can I just call you K.D. for short? /w3tcompact/icons/smile.gif) - I figure I use 75%-85% of my L4310's hp. It clearly has more hp than the transmission can put to the ground - IF, and only if, you really beef up the tires. Unless you do that, traction will be the limiting factor, by far, no matter what the conditions, even on concrete or asphalt.

These tractors are pretty bullet-proof, in my opinion. If you go to extremes to get enough traction, as I have, and you have the highest hp in the range, the relief valves in the transmission pop, just as they should.

MarkC