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Troubleshooting
WARNING
To reduce the risk of serious injury whenever you
are instructed to relieve pressure, always follow the
Pressure Relief Procedure on page 6.
Relieve the Pressure before you check or service any
system equipment.
NOTE: Check all other possible problems and solu-
tions before disassembling the pump.
Problem
Cause
Solution
Pump fails to operate
Restricted air line or inadequate air supply
Clear the line. See the Technical Data on page
11 for air volume requirements.
Insufficient air pressure
Increase air pressure – the pump will not oper-
ate below 30 psi (2.1 bar, 210 KPa) air pressure.
Closed or clogged valves or regulators on the air
and/or fluid side of the system.
Check the valves and regulators and adjust or
clean as needed.
Fluid has dried on the displacement rod
Clean. See displacement pump manual
308–043. Also, keep TSL in the pump wet-cup,
and stop the pump at the bottom of its stroke
during non-use.
Air motor is dirty, worn, or damaged
Service the motor. See manual 307–049. Be
sure the air supply is clean and dry, and that the
motor is properly lubricated.
Pump operates, but the fluid output is low on
both strokes
Empty fluid supply container
Refill the fluid supply container
p p
,
p
both strokes
Restricted air line or inadequate air supply
Clear the lines. See the Technical Data on page
11 for air volume requirements.
Insufficient air pressure
Increase air pressure – the pump will not oper-
ate below 30 psi (2.1 bar, 210 KPa) air pressure.
Fluid hose or gun is clogged
Clean the hose or gun, flush frequently.
Fluid is too heavy for the pump to prime
Use an inductor plate or ram.
Loose packing nut or worn throat packings
Tighten packing nut or replace packings as
needed. See manual 308–043.
Ball travel restricted too much for the viscosity of
fluid being pumped.
See Check Valve Adjustment in manual
308–043.
Pump operates, but the output is low on the
down stroke
Fluid is too heavy for the pump to prime
Use an inductor plate or ram.
p p
,
p
down stroke
Damaged cylinder o-rings
Replace o-rings. See manual 308–043.
The intake valve is stuck open or worn
Check; replace parts as needed. See manual
308–043.
Ball travel restricted too much for the viscosity of
fluid being pumped.
See Check Valve Adjustment in manual
308–043
Pump operates, but the output is low on the
upstroke
The piston valve is stuck open or the packings are
worn
Check, replace parts as needed. See manual
308–043
p
Damaged cylinder o-rings
Replace o-rings. See manual 308–043
Pumps is operating erratically, or speeds up
suddenly
Empty fluid supply container
Refill. Also see Operation on page 6.
p
p
g
y,
p
p
suddenly
Fluid hose or gun is clogged
Clean the hose or gun. Flush frequently.
The piston valve is stuck open or the packings are
worn
Check, replace parts as needed. See manual
308–043.
The intake valve is stuck open or worn
Check; replace parts as needed. See manual
308–043.
Loose packing nut or worn throat packings
Tighten packing nut or replace packings as
needed. See manual 308–043.