Troubleshooting; Mechanical/Fluid Flow - Graco 25R757 Operation, Parts

Troubleshooting

Mechanical/Fluid Flow

1. Follow Pressure Relief Procedure,
page 9, before checking or repairing.
Problem
Control board status light is blinking
or the light is off and there is power to
the sprayer.
Pump output is low
334641J
2.
What to Check
If check is OK, go to next
check
Fault condition exists.
Spray tip worn.
Spray tip clogged.
Paint supply.
Intake strainer clogged.
Intake valve ball and piston ball are
not seating properly.
Fluid filter or tip filter is clogged or
dirty.
Prime valve leaking.
Verify pump does not continue to
stroke when gun trigger is released.
(Prime valve not leaking.)
Leaking around throat packing nut
which may indicate worn or damaged
packings.
Troubleshooting
Check all possible problems and causes
before disassembling the unit.
When check is not OK,
refer to this column
Determine fault correction from
Electrical, page 26.
Follow Pressure Relief Procedure,
page 9, then replace tip. See
separate gun or tip manual.
Relieve pressure. Check and clean
spray tip.
Refill and reprime pump.
Remove and clean, then reinstall.
Remove intake valve and clean.
Check balls and seats for nicks;
replace if necessary. See pump
manual. Strain paint before using to
remove particles that could clog
pump.
Clean filter.
Follow Pressure Relief Procedure,
page 9, then repair prime valve.
Service pump. See pump manual.
Replace packings. See pump manual.
Also check piston valve seat for
hardened paint or nicks and replace if
necessary. Tighten packing
nut/wet-cup.
What to Do
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