Pressure Relief Procedure
To reduce the risk of serious bodily injury, including fluid injection, splashing in the eyes or on the skin, or injury from moving
parts, always follow this procedure whenever you shut off the pump, when checking or servicing any part of the spray system,
when installing, cleaning or changing spray tips or nozzles, and whenever you stop spraying or dispensing. (1) Engage the gun
safety latch. (2) Turn off the air to the pump. (3) Close the bleed-type master air valve (required in system). (4) Disengage the
gun safety latch. (5) Hold a metal part of the gun firmly to the side of a grounded metal pail, and trigger the gun into the pail to
relieve pressure. (6) Engage the gun safety latch. (7) Open the pump drain valve (required), having a container ready to catch the
drainage, and leave open until you are ready to spray again.
If you suspect that the spray tip, nozzle or hose is completely clogged, or that pressure has not been fully relieved after following
the steps above, wrap a rag around the tip guard retaining nut or hose end coupling and VERY SLOWLY loosen the part to
relieve pressure gradually, then loosen completely. Now clear the tip, nozzle or hose.
TROUBLESHOOTING CHART
NOTE:
Check all possible problems and solutions before disassembling the pump.
PROBLEM
Pump fails to operate
Pump operates, but output low on
both strokes
CAUSE
Exhausted fluid supply
Restricted line or inadequate air supply
Insufficient air pressure; closed or
clogged air valves, etc.
Obstructed fluid hose or gun
Dried fluid built up on displacement
rod
Dirty or worn air motor parts
Exhausted fluid supply
Restricted line or inadequate air supply
Insufficient air pressure; closed or
clogged air valves, etc.
Obstructed fluid hose or gun
Open or worn bleeder valve
Air leaking into fluid pressure
chamber of ram
SOLUTION
Refill
Clear; see TECHNICAL DATA on back
paw
Open; clean
Clear’
Clean; see pages 8 and 9
Clean; service (see 306968)
Refill
Clear; see TECHNICAL DATA on
back page
Open; clean
Clear*
Close; replace
Check ram plate seal, etc.
Fluid too heavy for pump to prime
Pump operates, but output low on
downstroke
Pump operates, but output low on
upstroke
Erratic or accelerated pump
operation
Worn throat packings in displacement
pump
Fluid too heavy for pump to prime
Held open or worn intake valve
Held open or worn piston valve or
packings
Exhausted fluid supply
Fluid too heavy for pump to prime
Held open or worn piston valve or
packings
Held open or worn intake valve
Worn throat packings in displacement
pump
Use bleeder valve; see OPERATION;
use ram units
Clear; service
Use bleeder valve; see OPERATION;
use ram units
Clear; service
Clear; service
Refill
Use bleeder valve; see OPERATION;
use ram units
Clear; service
Clear; service
Clear; service
*Follow the Pressure
Relief Procedure
above; disconnect the fluid hose. If the pump starts when the air is turned on, the hose, spray
gun or dispensing valve is clogged.
306-970 7