Enough fluid in tractor for dump trailer???

[jobguy]

I have a CT120 Bobcat tractor with remote hydraulics mounted behind the seat. I also have a dump trailer with a 12 volt hydraulic pump and fluid tank which do not work. How do I determine if there is enough fluid in the tractor reservoir to operate the dump trailer? Also the dump trailer has cheap fluid in it so I will need to flush that out somehow but with what? Any help is appreciated.

 

[20 20]

My dump trailer only uses a few quarts to dump all the way up{50degrees}. As far as flushing out the cylinder just colapse the cylinder{if it's gravity down}. That way all the fluid goes back into the holding tank on the eletric unit.

 

[kennyd]

You will be fine running it off the tractor-that tanks are big on CUT's. When the cylinder is collapsed there is very little fluid in it...should be no problem with contamination.

 

[jobguy]

Thanks: Another question.
The dump trailer only has one hose to it. When I hook up to one of the auxiliary quick connects and raise the dump, when gravity lowers the dump and my control lever is in neutral will fluid flow back to the tractor? If not what will I have to do to make this work?

 

[jinman]

The ideal situation with a dump trailer is to have double-acting cylinders so that it is powered both up and down. That way you use almost no extra fluid from your sump because fluid from the unpressurized side of the cylinder flows back to the reservoir while the pressurized side is extending or retracting. In your situation with one hose attached to your remote valve, the trailer will lower when you move the remote lever opposite the dump position, but the open center system will be interrupted and the tractor's hydraulic system will go into relief bypass. This may/will put stress on your tractor's hydraulic pump by keeping the system in relief for the length of time your trailer takes to lower. A better situation would be to "T" off the line to your trailer and go through another valve (call it a lowering valve) that returns directly to the sump through your filler plug opening. That way you'll use your remote for power to the trailer and return will go out the "T", thru the added "lowering valve" and into your tractor's sump.

 

[J_J]

I am thinking, that with the pump set upon the tailer, maybe that was a double acting cylinder, and when the hyd pump pushed it up, a solenoid let the fluid out. and the other inlet fitting had a breather on it to let air in and out. If it is a double acting cylinder on the trailer, the rear remotes should work the cylinder just fine. After the trailer bed is raised and lowered a couple of times, recheck the tractor fluid.

 

[jobguy]

The dump cylinder is a single acting cylinder. There is a electric up/down switch you hold in your hand. I believe the switch controls a relief valve that allows fluid to return to the reservoir through the same hose that is used to raise the box.

 

[jobguy]

Thank you for the information.
Where can I find an explanation of the open center system?.
I only use the dump a few times a year. Considering the few times the dump gets used, will the system stress in relief bypass be significant enough to make a difference?

 

[dfkrug]

The dump cylinder is a single acting cylinder. There is a electric up/down switch you hold in your hand. I believe the switch controls a relief valve that allows fluid to return to the reservoir through the same hose that is used to raise the box.

If you are looking at a common commercial hyd power pack, the control
lever will close a switch in one direction, and pushed the other way, it
opens a check valve that allows the oil in the SA cylinder to return to the
tank.

That is the way my Fenner-Stone power pack works (stolen off a hyd
lift gate). My cyl is used in a SA manner with a filter vent on one port,
but it is a DA cylinder if that port is pressurized.

 

[Diamondpilot]

It will work but just make sure you do not run the cut's reservoir dry while lifting it. Watch it the first time.

To drain the system just take off all the hoses and drain it out. You will get 95% out.

Chris