Has anyone ever

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Bob Norris

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Aug 4, 2006
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Evening, I have a nice trencher I built and will post pics and info later but being somewhat of an inventor I'm just wondering if anyone has ever done this Ive got a case 1835b. Its one of the best small skid steers ever made. Heres the deal. The trannies eventually kick the bucket and cost way to much to rebuild. Being a hydraulic freak I'm thinking of sh*t canning it and bolting the tandem pump right to the engine. Then using 25gpm 4 way valves control the drive motors and system hydraulics with joy sticks instead of levers. I personally hate foot controls and thats one reason I went with case. I have access to a few 1835's and 40's with bad trannies cheap. The parts to convert will be about $700, way more reasonable then a rebuilt trannie. I think it would be more efficient as well not to mention the ease of control of levers instead of handles connected to hydraulic valves. Any comments?
 

jerry

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I think I saw something like that in the Farm Show magazine where a guy built a skidsteer and ran it with a big pump and valves to control the motors I don't know if their archives are on line or not but it was interesting and looked fairly simple. Would it be just a straight pump or is it variable flow?
 
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Bob Norris

Bob Norris

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Aug 4, 2006
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I think I saw something like that in the Farm Show magazine where a guy built a skidsteer and ran it with a big pump and valves to control the motors I don't know if their archives are on line or not but it was interesting and looked fairly simple. Would it be just a straight pump or is it variable flow?
Id use the existing tandem pump, the valves would have power beyond and be open centers. I might even use one pump and control all hydrolics as its just motors and cylinders.
 

Tazza

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Id use the existing tandem pump, the valves would have power beyond and be open centers. I might even use one pump and control all hydrolics as its just motors and cylinders.
I have seen people in machine builders run their drive motors like that.
It would indeed be interesting. I see no reason why it can't be done, as long as you understand that with using fixed displacement pumps you won't have quite as much power at your disposal, the oil will get hotter faster as you aren't just pumping what you need, you are pumping 100% of the oil 100% of the time.
With that said, i see no reason it won't work! if you do it, i'm sure i'm not alone in saying i want pictures!
 
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Bob Norris

Bob Norris

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Aug 4, 2006
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I have seen people in machine builders run their drive motors like that.
It would indeed be interesting. I see no reason why it can't be done, as long as you understand that with using fixed displacement pumps you won't have quite as much power at your disposal, the oil will get hotter faster as you aren't just pumping what you need, you are pumping 100% of the oil 100% of the time.
With that said, i see no reason it won't work! if you do it, i'm sure i'm not alone in saying i want pictures!
"as long as you understand that with using fixed displacement pumps you won't have quite as much power at your disposal, the oil will get hotter faster as you aren't just pumping what you need, you are pumping 100% of the oil 100% of the time." Should be just as much power I would think?? I have dozer's backhoes and more that run lots of stuff off one pump. Besides, with ought that trannie takin up space I could have a cooler! ;)
 

Tazza

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"as long as you understand that with using fixed displacement pumps you won't have quite as much power at your disposal, the oil will get hotter faster as you aren't just pumping what you need, you are pumping 100% of the oil 100% of the time." Should be just as much power I would think?? I have dozer's backhoes and more that run lots of stuff off one pump. Besides, with ought that trannie takin up space I could have a cooler! ;)
Basically its producing wasted potential power. Most of the time the oil will be simply flowing back to the tank and doing nothing but generating heat. This is where variable displacement pumps shine, they only produce flow when needed.
As for less power, the hydrostatic pumps will produce up to 5,000 PSI, most fixed displacement ones go to around 3,000. At low drive speed i don't think you would have the same power and if you did, you would be loading the engine the same as if you were driving at top speed.
I am far from an expert on hydraulics, i know it would be far more efficient doing it with the pumps it has now but it will indeed work the way you describe. Don't let me talk you out of it, i want to see this! Just one thing to keep an eye on is that you don't use pumps that are too large for the engine to handle, if you get that rite, i see no reason why it won't work.
 
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Bob Norris

Bob Norris

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Aug 4, 2006
Messages
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Basically its producing wasted potential power. Most of the time the oil will be simply flowing back to the tank and doing nothing but generating heat. This is where variable displacement pumps shine, they only produce flow when needed.
As for less power, the hydrostatic pumps will produce up to 5,000 PSI, most fixed displacement ones go to around 3,000. At low drive speed i don't think you would have the same power and if you did, you would be loading the engine the same as if you were driving at top speed.
I am far from an expert on hydraulics, i know it would be far more efficient doing it with the pumps it has now but it will indeed work the way you describe. Don't let me talk you out of it, i want to see this! Just one thing to keep an eye on is that you don't use pumps that are too large for the engine to handle, if you get that rite, i see no reason why it won't work.
Neat, This loader has 2 separete 2gpm 2000psi pumps hooked up tandem. I think the main pump runs all the time and the drive motor pump (controled by the levers through the tranny) runs all the time too. I could be wrog. Here are the joy stick valves I'm looking at: http://stores.daltonhydraulic.com/-strse-242/Loader-Valve%2C-Mono-dsh-Block%2C-Prince%2C/Detail.bok Its got a 38 HP diesel engine so hooking it to a good sized pump should be a problem. Thanks for all the input. This is a great place to get info!
 
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Bob Norris

Bob Norris

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Aug 4, 2006
Messages
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Neat, This loader has 2 separete 2gpm 2000psi pumps hooked up tandem. I think the main pump runs all the time and the drive motor pump (controled by the levers through the tranny) runs all the time too. I could be wrog. Here are the joy stick valves I'm looking at: http://stores.daltonhydraulic.com/-strse-242/Loader-Valve%2C-Mono-dsh-Block%2C-Prince%2C/Detail.bok Its got a 38 HP diesel engine so hooking it to a good sized pump should be a problem. Thanks for all the input. This is a great place to get info!
20GPM not 2 GPM ;)
 
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