Multiquip manual LS400/LS500 Pump Troubleshooting Pump

LS400/LS500 PUMP — TROUBLESHOOTING (PUMP)

The hydraulic troubleshooting procedures listed below are intended for use by individuals equipped with the proper tools and equipment and are familiar with hydraulic systems and safe shop practices. Use the Pump Troubleshooting Table (Table 8) to identify possible causes for the pump’s malfunction. Contact the Multiquip Service department for the proper repair procedure.

DANGER - AMPUTATION RISK

During routine maintenance or removing material blockage, you will be required to put your hand in the concrete cylinders or near the shuttle tube.You are at EXTREME RISK of injury or AMPUTATION if the engine is running or if pressure is in the hydraulic system.

Prior to performing any maintenance on the pump, follow described lock out-tag out procedures. Stop the engine by turning off the ignition switch and remove the starter key. Place a “DO NOT OPERATE” tag over the switch and disconnect the battery. The pressure reading on the

accumulator pressure gauge MUST read ZERO. ALWAYS make sure the accumulator circuit pressure reads

zero prior to performing any maintenance on the pump.

WARNING - HYDRAULIC SYSTEM HAZARD

DO NOT open hydraulic lines or loosen hydraulic fittings while the engine is running! Hydraulic fluid under pressure can penetrate the skin, blind, cause burns or create other potentially dangerous hazards.

TABLE 9. PUMP TROUBLESHOOTING

Problem	Possible Problem	To Troubleshoot
	Incorrect System Operating	Check the pump pressure gage. Verify
	Pressure	it is approx. 4400 PSI
	Incorrect Engine RPM setting	Verify the engine's high RPM speed is
Main Hydraulic Cylinder will		set to 2550
not cycle	Contaminated Main Relief Valve	Check the manifold for a contaminated
		Relief Valve
	Obstructed Material Cylinders	check for obstructions (dried material)
		inside the cylinders
	Incorrect Directional Control	Verify the Directional Control operating
	Operating Pressure	pressure is approx. 1000 PSI
	Contaminated Relief Valve	Check the manifold for a contaminated
Hopper Remix Paddles will		Relief Valve
not rotate	Broken Shaft Coupler Key	Check the Hopper Remixer shaft
		coupler for a broken key
	Loose Shaft Retaining Set Collar	Check the Shaft Retaining Set Collar
		for tightness

PAGE 62 — MAYCO LS400/LS500 PUMP — OPERATION AND PARTS MANUAL — REV. #6 (09/19/11)