Hydrostatic vs. Manual pro's and con's

KiotiJohn · May 18, 2005

Re: Hydrostatic vs. Manual pro\'s and con\'s

( Now in some cases the relief valve may well need to be set where it is to protect the rest of the chassis (axles, final drives) despite the extra engine power of a bigger model. )
I think the relief is protecting the hydraulic system more than the axles, etc. Otherwise, the gear versions would wreak havoc on those systems. Hyrdro hoses, pumps etc. benefit from pressure relief.
John

Varmintmist · May 18, 2005

Re: Hydrostatic vs. Manual pro\'s and con\'s

( Um... isn't a power shuttle lever more-or-less in effect hand clutch? Thought about that one day when flipping directions - something along the lines of what was old is new again. /forums/images/graemlins/wink.gif )

Only in placement. There is no finess in using the reverser, the hand clutch on the other hand....

slowzuki · May 18, 2005

Re: Hydrostatic vs. Manual pro\'s and con\'s

You have introduced torque and hp and drawbar power and pull all in one post.

The relief governs the maximum possible torque transmitted through the hydro.

This in turn governs the max possible drawbar pull in theory. It may be the tractor is too light to develop the max drawbar pull and has wheel slip.

Once moving at some point you are not devloping maximum torque anymore as the engine can only deliver a certain amount of power. This means the tractor at higher speeds will not hit a relief situation but rather be governed by the engine torque.

This means the drawbar power is limited by engine power too.

Max PTO power is unaffected by relief valves and such.

( hydro relief setting was the same across all of the TC35-40-45 models. That meant that while the TC45D still had more PTO hp than the TC40D or TC35D models, it can't put any more power *to the ground* than the TC35D. )

thcri · May 18, 2005

Re: Hydrostatic vs. Manual pro\'s and con\'s

( Do you know where the thread is? I don't think that was what happened, because I seem to remember that he put more oil in it and it still wouldn't climb out. )

I think the thread was "What's ailing my Kubota" One of the longest threads here on TBN. But the way this one is going it will get right up there??

murph /forums/images/graemlins/grin.gif /forums/images/graemlins/grin.gif

jeffinsgf · May 18, 2005

Re: Hydrostatic vs. Manual pro\'s and con\'s

( Huntsville. I like your Race Brothers store. We have one, but they don't carry near as much as yours. There is a farm store west of Race Brothers. They had some really good prices. What is their name? )

SoMo Supply. Good folks, too. Give me a holler next time you're in Springfield.

Soundguy · May 18, 2005

Re: Hydrostatic vs. Manual pro\'s and con\'s

 Um... isn't a power shuttle lever more-or-less in effect hand clutch? Thought about that one day when flipping directions


I wouldn't consider it any more of a hand clutch than a range selector would be.. even though on the range selector you could shift out of a range and then not into a range, and have no wheel movement..but you would still need foot clutching action to make the range selector selection.. etc.

Soundguy

timb · May 18, 2005

Re: Hydrostatic vs. Manual pro\'s and con\'s

Different shuttle systems may operate very differently - but on my (Deere) PRT tranny - the 3-position (forward-neutral-reverse) dash-mount shuttle lever, via linkages, controls a couple of valves in a valve body on the tranny. Depending on the position of the linkage - either the forward or the reverse clutch pack is engaged (or nether in neutral).

The "clutch" pedal on the deck - via linkages - operates related valves in the same valve body - operates the same clutch packs, but only choosing between engaged/disengaged settings for whatever pack the shuttle lever has targeted.

The diagram of the actual combinations/permutations of fluid flows through the valve body in the different modes seems to rival an automatic transmission in a car!

In any case - since it drives the same clutch packs as the foot pedal - it seemed like it was in some sense a hand clutch of a sort. Although not nearly as much "fun" to operate as some of the stories I've heard of the old true hand clutch tractors. Never had the pleasure to run one of those.

Soundguy · May 18, 2005

Re: Hydrostatic vs. Manual pro\'s and con\'s

My B has a hand clutch. Hard to get over stomping the left brake before you do something.

What's realy interesting are those tractors with a main foot clutch, and then a hand clutch ( usually only clutching an axle.. etc ) and that kinda gives you 'live pto'.

Soundguy

Cactus · May 18, 2005

Re: Hydrostatic vs. Manual pro\'s and con\'s

Heres the link....

JerryG · May 18, 2005

Re: Hydrostatic vs. Manual pro\'s and con\'s

 had a partial check on tractor today by a fellow who is a tractor technician for a farm equipment co....but he is a New Holland guy..not Orange. Says everything looks ok as far as he can tell, no leaks, or any malfunction on pumps and reservoir. I think he agrees that maybe something happened with the hyd. log splitter and maybe i just happen to get it in a 'freaky' position on that slope where the fluid just got below the top of intake and air got in it...but...anyway, I'll not be using it until i get it to Kubota dealer.
Once again, thanks guys...thanks so much for the support.

This was his last post on the subject. The NH guy thought that maybe the pickup got above the fluid, but he didn't know. Whether it was blowing the relief or the pickup above the fluid level because of the acute angle of getting out, it was a problem that only a hydro could have had.