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Troubleshooting
3A0231F
19
Troubleshooting
Schematics
For standard machines,
the schematics will be
included in the 4104A Parts manual.
For custom machines,
the schematics will be included
in the assembly drawings manual.
Perform
before perform-
ing any troubleshooting procedure.
Problem
Cause
Solution
Metering valve stalling and no mate-
rial being dispensed despite ade-
quate input pressure
Blocked needle
Check needle for cured material,
replace as required
Flow control valve closed
Open needle
Metering valve not discharging nor-
mal or full volume
Low material level in reservoirs
Fill material reservoirs and prime the
machine
Air in material tank
Fill reservoir and prime machine
Material leaks past spool valve
Spool valve worn or damaged
Replace the spool valve
Spool will not actuate
Low air pressure
Increase air pressure to approxi-
mately 20-30 psi
Cured material on spool
Check spool for cured material,
replace as required
Seals are worn
Replace seals