Graco DURON Performance Max 395 Repair Manual page 10

LOW OR FLUCTUATING OUTPUT
TYPE OF PROBLEM
Motor runs and pump strokes
Motor runs but pump does not
stroke
10 309714
Troubleshooting
WHAT TO CHECK
If check is OK, go to next check
1. Paint supply.
2. Intake strainer clogged.
3. Suction tube or fittings loose.
4. To see if intake valve ball and piston ball are
seating properly. See page 21.
5. Leaking around throat packing nut which may
indicate worn or damaged packings. See
page 21.
6. Pump rod damage.
1. Displacement pump pin (32) (damaged or
missing), page 21.
2. Connecting rod assembly (43) for damage,
page 19.
3. Gears or drive housing, page 19.
WHAT TO DO
When check is not OK refer to this column
1. Refill and reprime pump.
2. Remove and clean, then reinstall.
3. Tighten; use thread sealant or sealing tape
on threads if necessary.
4. Remove intake valve and clean. Check
balls and seats for nicks; replace if neces-
sary, page 21. Strain paint before using to
remove particles that could clog pump.
5. Replace packings, page 21. Also check
piston valve seat for hardened paint or
nicks and replace if necessary. Tighten
packing nut/wet-cup.
6. Repair pump, page 21.
1. Replace pump pin if missing. Be sure re-
tainer spring (31) is fully in groove all
around connecting rod, page 21.
2. Replace connecting rod assembly,
page 19.
3. Inspect drive housing assembly and gears
for damage and replace if necessary,
page 19.