Troubleshooting; Mechanical / Fluid Flow - Graco Mark V Premium Repair Manual

Troubleshooting

Troubleshooting

Mechanical / Fluid Flow

Perform Pressure Relief Procedure; page 9. Wait 5 minutes before servicing.
TYPE OF PROBLEM
ERROR=XX is displayed
Pump output is low
Pump output is low
10
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, tip filter, or tip 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.
Pump rod damage
Low stall pressure
Piston packings are worn or dam-
aged
O-ring in pump is worn or damaged
Intake valve ball is packed with mate-
rial
Pressure setting is too low
Large pressure drop in hose with
heavy materials
WHAT TO DO
When check is not OK, refer to this column
Determine fault correction from table,
page 12.
Follow Pressure Relief Procedure on page 9,
then replace tip. See your 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; see operation manual.
Relieve pressure. 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 pack-
ing nut/wet-cup.
Repair pump. See pump manual.
Turn pressure knob fully clockwise. Make sure
pressure control knob is properly installed to
allow full clockwise position. If problem per-
sists, replace pressure transducer.
Replace packings; see pump manual.
Replace o-ring; see pump manual.
Clean intake valve; see pump manual.
Increase pressure; see pump manual.
Use larger diameter hose and/or reduce overall
length of hose.
3A2333B