Hitachi 308640 manual General Troubleshooting, Problem, Cause, Solution

Troubleshooting

WARNING

INJECTION HAZARD

To reduce the risk of a fluid injection injury, follow the Pressure Relief Proce- dure on page 7 before checking or

servicing any of the system equipment and when- ever you are instructed to relieve pressure.

NOTE:

DCheck all possible remedies in the troubleshooting charts before disassembling the gun.

DSome improper patterns are caused by the improper balance between air and fluid.

General Troubleshooting

Problem

Fluid leakage from back of fluid needle

Air leakage from front of gun

Fluid leakage from front of gun

Fluid in air passages

Slow fluid shut-off

Cause

Worn packings or needle shaft

Air valve not seating properly

Fluid needle worn or damaged

Worn diffuser-seat housing

Fluid tip seal leaking

Leaking around diffuser-seat housing

Fluid inlet fitting leaking

Fluid buildup on fluid needle cartridge components.

Diffuser-seat is overtightened.

Solution

Replace external needle packings or entire fluid needle cartridge. See page 16.

Clean/service air valve. See page 16.

Replace fluid needle cartridge. See page 16.

Replace the diffuser-seat and gasket. The gasket must be replaced when- ever the diffuser-seat is removed. See page 16.

Tighten or replace fluid tip.

Replace the diffuser-seat gasket. The gasket must be replaced whenever the diffuser-seat is removed. See page 16.

Replace the fluid fitting gasket. The gasket must be replaced whenever the fluid fitting is removed. See page 17.

Remove and clean or replace the fluid needle cartridge. See page 16.

Remove diffuser-seat and replace diffuser-seat gasket. Torque diffuser- seat to 90±100 in-lb (10.2±11.2 NSm).

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