Hitachi 312350E Troubleshooting, Problem, Cause, Solution, Relieve pressure, page 7. Check

		Troubleshooting
Troubleshooting
Problem	Cause	Solution
Pump does not run.	Closed dispense valve.	Pump only runs with valve open.
	Pressure too low.	Increase supply pressure using a
		pressure adjusting valve.
	Insufficient hydraulic fluid supply.	Check hydraulic supply. Adjust to a
		maximum of 3 gpm (11 lpm) flow.
	Clogged fluid outlet line, intake valve,	Relieve pressure, page 7. Check.
	dispense valve, suction line.	Clear obstructions.
	Reciprocator damaged.	Repair.
Pump speeds up or runs erratically.	Pump piston and/or intake valve	Relieve pressure, page 7. Check
	worn.	and repair.
	Empty supply container.	Refill and repair. Do not allow pump
		to run dry. Monitor closely or use a
		low-level cutoff valve.
Pump runs but output low on up	Pump piston and/or intake valve	Relieve pressure, page 7. Check
and/or down stroke.	worn.	and repair.
Pump run but output low on both up	Insufficient hydraulic fluid supply.	Check hydraulic supply. Adjust to
and down strokes.		maximum 3 gpm (11 lpm) flow.
	Pressure too low.	Increase supply pressure using a
		pressure adjusting valve.
	Clogged fluid outlet line, intake valve,	Relieve pressure, page 7. Check.
	dispense valve, suction line.	Clear obstructions.
Excessive weepage from weep tube	Worn throat packings.	Repair.
(B), page 4.
	Worn displacement seal.	Repair.
Hydraulic oil leaks from fittings in the	Fittings 1, 5, 58, (Parts, page 18), are	Tighten the self-sealing fittings. If
upper or lower reciprocator blocks	loose, or their o-rings are worn or	leaking persists, change o-rings.
(31, 32) [Parts page 18].	damaged.

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