Graco GT 750, Instructions Manual

Page: 7 / 18

Troubleshooting
3A5363B 7
Troubleshooting
NOTE: Check all other possible problems and solutions before you disassemble the pump.
Problem Cause Solution
Pump fails to operate or there is no
fluid flow
Inadequate air supply pressure Increase air supply.
Restricted air line Clear line.
Closed dispensing valve Open valve.
Clogged fluid lines, hoses, and/or
dispense valve
1. Follow Pressure Relief Proce-
dure, page 6.
2. Disconnect fluid line.
3. Turn on air. If the pump starts
when the air is turned again, the
line, hose, and/or valve is
clogged. Clear obstruction.
Damaged air motor Service air motor. See SaniForce Air
Motor manual.
Exhausted fluid supply Refill and prime or flush.
Continuous air exhaust Worn or damaged air motor gasket,
packing, seal, etc. Service air motor. See SaniForce Air
Motor manual.
Erratic pump operation
Exhausted fluid supply Refill and prime or flush.
Held open or worn intake valve or
piston seals Replace worn seals. See Service,
page 8.
Inadequate air supply pressure Increase air supply.
Pump operates but output low on
down stroke Held open or worn intake valve or
piston seals Replace worn seals. See Service,
page 8.
Fluid is coming out of the muffler Worn or damaged throat seal Replace worn seals. See Service,
page 8.