roadhunter
Elite Member
I have an attachment that is building an incredible amount to heat in the hydraulics when I operate. I don't' exactly understand what causes heat in hydraulic systems so I thought I would throw this out there and see if anyone can shed some light on this subject.
The machine only has 4 hydraulic circuits.
#1 controls the drive wheels. This valve is always open and has an adjustment to control the wheels speed.
#2 and #3 adjust the spacing of the drive wheels and the angle. These only operate when the handle is pulled
#4 operates the arm on the top drive wheel and has a pressure regulator to adjust the down pressure on the cylinder.
According to the manufacturer this requires 8 GPM of flow to operate. The unit has a pressure regulator and a flow divider installed but strangely I can still build over 2,000 PSI if I open the valve on the tractor even at idle. That makes me think the pressure regulator and flow divider is not working as taht should not be possible. Makes me think there is a restriction in the system causing all the back pressure.
I tried operating this with my old famrall with a PTO hydraulic pump. Input pressure was 900 PSI and the oil overheated to 190+ in less than 10 minutes with no load. IT only has about a 4 gallon tank so the heat had nowhere to go.
When I operate it with my JCB wint 900 PSI of input pressure the oil goes to 175+ in about 20 minutes. Keep in mind this has a large reservoir and oil cooler on the motor.
According to the manufacturer, Rabaud, they say this is normal for the Robopel 250. Everyone I have talked to said that building that much heat is not normal, especially when not under a heavy load.
I guess I'm trying to figure out how hydraulic oil builds heat and where I should look to try to pinpoint the problem. Here are some pics of the machine and valve.
Is the heat normally built in the pump or more likely in things like drive wheels that require constant flow? What about the circuit that has a pressure regulator, can the regulator cause heat buildup?
The machine only has 4 hydraulic circuits.
#1 controls the drive wheels. This valve is always open and has an adjustment to control the wheels speed.
#2 and #3 adjust the spacing of the drive wheels and the angle. These only operate when the handle is pulled
#4 operates the arm on the top drive wheel and has a pressure regulator to adjust the down pressure on the cylinder.
According to the manufacturer this requires 8 GPM of flow to operate. The unit has a pressure regulator and a flow divider installed but strangely I can still build over 2,000 PSI if I open the valve on the tractor even at idle. That makes me think the pressure regulator and flow divider is not working as taht should not be possible. Makes me think there is a restriction in the system causing all the back pressure.
I tried operating this with my old famrall with a PTO hydraulic pump. Input pressure was 900 PSI and the oil overheated to 190+ in less than 10 minutes with no load. IT only has about a 4 gallon tank so the heat had nowhere to go.
When I operate it with my JCB wint 900 PSI of input pressure the oil goes to 175+ in about 20 minutes. Keep in mind this has a large reservoir and oil cooler on the motor.
According to the manufacturer, Rabaud, they say this is normal for the Robopel 250. Everyone I have talked to said that building that much heat is not normal, especially when not under a heavy load.
I guess I'm trying to figure out how hydraulic oil builds heat and where I should look to try to pinpoint the problem. Here are some pics of the machine and valve.
Is the heat normally built in the pump or more likely in things like drive wheels that require constant flow? What about the circuit that has a pressure regulator, can the regulator cause heat buildup?
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