Troubleshooting
3A6393D
21
Troubleshooting
1. Follow the
on page 18.
2. Check all possible problems, causes, and solutions
listed below before disassembling the pump.
NOTE:
For troubleshooting and repair questions,
contact your distributor.
Mechanical/Fluid Flow
Problem
Cause
Solution
Displacement pump operates, but
output is low on upstroke
Piston ball check not seating properly Service piston ball check
Piston packings worn or damaged
Replace packings
Displacement pump operates, but
output is low on down stroke and/or
on both strokes
Piston packings worn or damaged
Tighten packing nut or replace
packing
Outlet check valve not seating
properly
Clean check valve
Intake valve ball check not seating
properly
Service intake valve ball check
Rubber elbow air leak
Tighten clamps
Fluid hose on the applicator is
obstructed
Clean the fluid hose on the applicator
Material leaks and runs over the side
of the wet cup
Loose wet cup
Tighten wet cup enough to stop
leakage
Throat packings worn or damaged
Replace packings
Fluid delivery is low
Applicator tip is dirty or clogged
Clean or replace
Clamps on hopper elbow are loose
Tighten clamps on hopper elbow
Large pressure drop in fluid hose
Reduce length or increase diameter
Electric motor does not operate
Power switch is not ON
Turn the power switch ON
Tripped circuit breaker
Check circuit breaker at power
source. Reset motor switch.
Sprayer does not operate
Fluid hose or applicator obstructed
Clean hose or application
Dried fluid on displacement rod or
inlet ball
Clean rod. Always stop pump at
bottom of stroke; keep wet cup filled
with TSL. Be sure the inlet ball
moves freely.
Erratic accelerated speed
Material supply exhausted, clogged
suction
Refill hopper and prime pump
Open or worn piston valve or
packings
Clear piston valve; replace packings
Open or worn intake valve
Clear or service intake valve
Cycles or fails to hold pressure at
stall
Worn check balls, seats, or piston
packing
Service lower
