Troubleshooting - Graco GT 750 Instructions Manual

Troubleshooting

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