Graco 25U546, Manual

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Troubleshooting
30 3A9031A
Troubleshooting
Mechanical/Fluid Flow
1. Follow Pressure Relief Procedure ,
page 10, before checking or repairing.
2. Check all possible problems and causes
before disassembling the unit.
Problem
What to Check
If check is OK, go to next
check
What to Do
When check is not OK,
refer to this column
Pump output is low Spray tip worn. Follow Pressure Relief
Procedure , page 10, then
replace tip. See separate gun
or tip manual.
Spray tip clogged. Relieve pressure. Check and
clean spray tip.
Paint supply. Refill and reprime pump.
Intake strainer clogged. Remove and clean, then
reinstall.
Intake valve ball and piston
ball are not seating properly.
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.
Fluid filter or tip filter is
clogged or dirty.
Clean filter.
Prime valve leaking. Follow Pressure Relief
Procedure , page 10, then
repair prime valve.
Verify pump does not continue
to stroke when gun trigger is
released. (Prime valve not
leaking.)
Service pump. See pump
manual.
Leaking around throat packing
nut which may indicate worn
or damaged packings.
Replace packings. See pump
manual. Also check piston
valve seat for hardened paint
or nicks and replace if
necessary. Tighten packing
nut/wet-cup.
Battery has insufficient charge. Charge battery.