I have an old homebuilt splitter with an Opel car engine and tranny that turned a large Gerotor hydraulic pump. The engine is more trouble than I want to fool with so I thought about running it with a pto shaft off a tractor. If I keep it simple the pump would turn backwards which a friend thinks is doable just by changing the hoses, is he right? It won't get used too often so I don't want to spend much on the experiment.
Most pumps have a direction of flow arrow or other markings stamped or molded on the housing indicating they are uni-directional. I don't recall ever working with a bi-directional pump....
If the pump ports are the same size, then maybe. If they are not the same size, the pump is likely directional and may be compromised if you run it backward. Some directional pumps can be easily disassembled to reverse flow.
Was the original gearbox running in reverse gear?
Got photo of pump/splitter?
In the past I had worked with some Commercial sherring and eaton gerotor motors. In some cases gerotors can be used as a pump. A straight out pump is more effecient in output without excessive heat production. But I have used the gerotor as a motor or pump...using the very same unit. And it worked well.
SOME OF THOSE UNITS MAY NOT BE SUITABLE because they are axial-torque units. That means they must be mounted inline with the power / use source. Others can have a heavy side thrust bearing so that one could incorporate a pulley drive system. The inline units typically have SAE shafts. I THINK YOU CAN BET THE HOUSE on a four bolt unit to be an in-line thing, with absolutely no side thrust capability.
David G
carry on
The tag says Gerotor hydraulic pump. I "think" but am not sure that the pump and cylinder are off an old Cat dozer, the input shaft on the pump is 1" with 1" npt fittings. The cylinder is 5" and I think 32" stroke. Back when the little Opel 4 cylinder ran I used it at half throttle with the tranny in second gear so it wasn't spinning too fast. It hasn't run in a few years and I just thought I would try to use it again except powered off a tractor pto. If I can't get it going cheap I'll scrap it.
I have tried the same thing but the pump was designed to flow one direction only .lets just say it was a dismal failure .lol. You live you learn .i dont remember what pump it was ,since you have the tranny all ready there could you just hook up your pto to the input shaft of your tranny and put it in reverse
Quote from: furltech on August 04, 2014, 06:38:31 PM
I have tried the same thing but the pump was designed to flow one direction only .lets just say it was a dismal failure .lol. You live you learn .i dont remember what pump it was ,since you have the tranny all ready there could you just hook up your pto to the input shaft of your tranny and put it in reverse
I like the way you think, use what you got. To do it that way would drop the already low rpms even lower so maybe hook the pump to trannys input and pto to the output? First I will still pursue the possibility of spinning the pump backwards.
I finally got around to testing this and yes you can turn it in reverse although you must also swap hoses. The lower rpm of the tractor pto keeps the cycle time down but I'm not all that fast anymore either. It has a 32" stroke but most of my wood is cut about 18" so that will help if I only retract 20".