TROUBLESHOOTING GUIDE

WARNING

Pressure Relief Procedure

To reduce the risk of serious bodily injury, including fluid injection, splashing in the eyes or on the skin, or injury from moving parts, always follow this procedure when you shut off the sprayer, when checking, adjusting or cleaning the system, and when changing spray tips.

1.Engage the gun safety latch.

2.Turn the ON/OFF switch to OFF.

3.Unplug the power supply cord.

4.Disengage the gun safety latch. Hold a metal part of the gun firmly to the side of a grounded metal pail, and trigger the gun.

5.Engage the gun safety latch.

6.Open the fluid pressure drain valve and leave it open until you start the sprayer again.

If you suspect the hose or spray tip is completely clogged or that pressure is not fully relieved after fol- lowing the steps above, VERY SLOWLY loosen the tip guard retaining nut or hose end coupling and relieve pressure gradually. Now clear the tip or hose.

Check everything in the chart before disassembling the sprayer.

PROBLEM

CAUSE

SOLUTION

 

 

 

Electric motor won't run

Power cord or extension cord unplugged,

Check, reset or replace.

 

or damaged, or building circuit breaker or

 

 

fuse has tripped

 

 

 

 

 

Motor overload switch1 has opened

Unplug power supply cord, relieve pressure, al-

 

 

low motor to cool, decrease pressure.

 

 

 

 

Pressure setting too low

Increase pressure.

 

 

 

 

Pressure control frozen2 or damaged by

Try to thaw, or replace pressure control.

 

over±pressurization3

 

Electric motor stops while spraying

Power cord or extension cord unplugged,

Check, reset or replace.

 

or damaged, or building circuit or fuse is

 

 

blown

 

 

 

 

 

Motor overload switch1 has opened

Unplug power supply cord, relieve pressure, al-

 

 

low motor to cool, decrease pressure.

 

 

 

 

Pressure setting too low

Increase pressure.

 

 

 

 

Spray tip or filter plugged

Remove and clean.

 

 

 

 

Wrong type extension cord

Use maximum 200 ft (61 m), 3 wires, 12 gauge,

 

 

grounded extension cord.

 

 

 

Electric motor runs, but low paint

Piston ball check not seating

Service the pump. See page 16.

output or no paint output;

 

 

or pump is not stroking

 

 

See the PROBLEM, ªNot enough

 

 

Piston packings worn or damaged

Replace the piston. See page 16.

paint pressureº, on page 15, also

 

 

 

 

 

 

Intake valve ball check not seating

Service the pump. See page 16.

 

 

 

.

Pump is frozen

Thaw2

 

Filter element installed upside down

Install element correctly. See page 12 or manual

 

 

307±273.

 

 

 

 

Pressure control frozen2 or damaged by

Try to thaw, or replace pressure control.

 

over±pressurization3

 

 

Drive assembly damaged

Replace drive housing. See page 19.

 

 

 

 

Displacement pump worn or damaged

Replace displacement pump. See page 16.

 

 

 

 

Sprayer is not primed.

Prime sprayer. See page 10.

 

 

 

Electric motor labors when starting,

Motor capacitor has failed

Replace the capacitor. See page 20.

and trips building circuit breaker or

 

 

fuse

 

 

 

 

 

 

Circuit board has failed

Replace the circuit board. See page 21.

 

 

 

14307-735

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Hitachi EM 490 dimensions Troubleshooting Guide, Pressure Relief Procedure, Problem Cause Solution