Hydraulic Trainers Flashcards
Check valve
Hook the micro leak to 2 and gauge on 1 and if the gauge builds pressure the check is blowing through and therefore bad.
Single rod cylinder
Take away all other flow paths and hook the micro leak to the rod end and if the rod advances outward the seal is bad.
Motor starting pressure control
If the motor engages when the double rod picks up the weight the valve is blowing through and bad or test flow on 2 to se if it’s blowing by early. (Can cause the double rod to leak very slowly)
Pilot relief
Hook a flow meter on 2 to tank or put a gauge on 3 to see premature valve opening.
Double rod
Hook the out going flow path to a ball valve and hook the other end to the counter balance where it was before to isolate the cylinder. If the cylinder continues to leak quickly after the flow path is isolated, the cylinder is bad. (The motor start valve, bad cylinder and bad counter balance can all cause leak down.)
Pressure reducing
Either hook a gauge to the blind end of the single rod or 1 on the reducing valve to see if it is exceeding the set pressure.
Motor
If the motors flow rate going in stays the same and the rpm goes down the motor is bad.
DCV(float center)
Hook the splitter from A or B port to the top of the flow meter and hook a hose from the port in question to the bottom of the flowmeter and monitor the flow leaving the DCV. If you’ve verified the pump is good the DCV has a bad port.
Sequencing valve
Hook a flow meter up to the outlet of the sequencing valve and look for any early flow spike on the extend or retract (I’ve only seen it on the retract on Chad’s print)
Counter balance
Hook a ball valve or flow meter to port #2 and see if flow is blowing back through the wrong direction and isolate or monitor it to diagnose.
DCV(blocked center)
Use microleak to pump up the ports on your dcv. If there is little to no resistance to the pump handle the port is blowing by.
