OMA107843

Symptom	Problem	Solution
Shaft seal on hydraulic motor forced off its seat.	Return pressure too high. Pressure and return lines inadvertently interchanged.	Max. return line pressure is 1500 kPa (15 bar; 217 psi); clean the couplers and connect correctly.

Return pressure too high.

Unfavourably routed oil return line; cross-section too small.

Re-route return line in tractor; use larger diameter lines and couplers.

Oil leaking from hydraulic motor.

Shaft seal either worn or fitted wrong way.

Install new shaft seal.

Insufficient speed.

Incorrect setting of three-way flow control valve; tractor not supplying sufficient oil or not generating required pressure.

Check the three-way flow control valve; check the hydraulic pump; check the pressure-relief valve.

Hydraulic motor cuts out for short periods at a time.

Unfavourably routed oil return line; insufficient oil in reservoir; oil returning via SCV.

Select a different connecting point for the zero-pressure return line; larger oil reservoir.

Pressure peaks in pressure line.

Drive output of pneumatic system too high.

Connect up all hose lines belonging to the pneumatic system of the drill.

Valve lever jumps out of its engaged position.

Pressure peaks in pressure line; cut-off pressure too low; pressure in pressure line too high.

Check setting; use pipes.

Hydraulic oil overheating.	High delivery rate.	Install additional oil cooler.
	Delivery rate too high (in the case of closed-center hydraulic system)	Remedy the problem by means of variable displacement pump; install or convert three-way flow control valve.

ZX,OM740A008592-19-20160122