Norton Abrasives C6136 Partially clogged suction filter, A bad front pump seal, A. Low Voltage

B. On systems that fail to prime or lose their prime, check for the following:

1.Correct unit mounting position in the case of a pump motor combination. It is either horizontal or vertical and failure to mount in proper manner could mean pump cannot prime (pick up oil) because the suction tube is not submerged in the oil at all times. Note: All pumps designed for vertical mounting have a label stating such.

2.Partially clogged suction filter.

3.A loose or improperly installed suction hose or pick up tube.

4.A bad front pump seal.

5.A solid fill plug in reservoir with no vent.

6.Oil that is too thick (See Hydraulic Fluid Section), or commercial with water.

7.Occasionally a pump will not prime itself because a check valve spring in the high pressure port is too "stiff" or the spring retainer is turned down too far. If this condition is expected, loosen the spring retainer, (it is found in the 3/8 high pressure outlet port), energize the pump to prime it, and then turn the retainer back to the correct depth. (See Section on Check Valves.)

12.Hydraulic Pump Electrical Problems

Warning: Remove all rings, watches, etc. prior to doing any electrical work.

A. Low Voltage

Operating direct current (DC) power units efficiency requires proper voltage. Any attempt to operate below the minimum required voltage could cause system failure. Signals which point to low voltages are:

1.Motor running at reduced speed.

2.Solenoid valves not shifting.

B.Minimum voltage readings are as follows:

1.The minimum voltage between the motor stud and ground is 9.0 volts at maximum load conditions.

2.The minimum voltage between the valve solenoid power wire ("hot wire") and ground is 9.5 volts at maximum load conditions.

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