Troubleshooting
3A4587B Operation, Repair, Parts
23
Problem
Cause
Solution
Pump output is low
Strainer (56) is clogged
Clean strainer.
Piston ball (206) is not seating
Service piston ball. Manual 309250.
Piston packings are worn or damaged
Replace packings. Manual 309250.
O-ring (227) in pump is worn or damaged Replace o-ring. Manual 309250.
Intake valve ball is not seating properly Clean intake valve. Manual 309250.
Intake valve ball is packed with material Clean intake valve. Manual 309250.
Engine speed is too low
Increase throttle setting.
Clutch is worn or damaged
Adjust or replace clutch. Page 9.
Pressure setting is too low
Increase pressure.
Fluid filter (104) or tip is clogged or
dirty
Clean filter or clear tip.
Large pressure drop in hose with
heavy materials
Use larger diameter hose and/or
reduce overall length of hose. Use of
more than 100 ft of 1/4 in. hose signifi-
cantly reduces performance of sprayer.
Use 3/8 in. hose for optimum perfor-
mance (50 ft minimum).
Excessive paint leakage into throat
packing nut
Throat packing nut is loose
Remove throat packing nut spacer.
Tighten throat packing nut just enough
to stop leakage.
Throat packings are worn or damaged Replace packings. Manual 309250.
Displacement rod is worn or damaged Replace rod. Manual 309250.
Fluid is spitting from gun
Air in pump or hose
Check and tighten all fluid connections.
Reprime pump.
Tip is partially clogged
Clear tip. Page 17.
Fluid supply is low or empty
Refill fluid supply. Prime pump. Check
fluid supply often to prevent running
pump dry.
Pump is difficult to prime
Air in pump or hose
Check and tighten all fluid connections.
Reduce engine speed and cycle pump
as slowly as possible during priming.
Intake valve is leaking
Clean intake valve. Be sure ball seat is
not nicked or worn and that ball seats
well. Reassemble valve.
Pump packings are worn
Replace pump packings. Manual 309250.
Paint is too thick
Thin the paint according to the sup-
plier's recommendations
Engine speed is too high
Decrease throttle setting before prim-
ing pump.
Clutch squeaks each time clutch
engages
Clutch surfaces are not matched to each
other when new and may cause noise
Clutch surfaces need to wear into each
other. Noise will dissipate after a day of
run time.
High engine speed at no load
Misadjusted throttle setting
Reset throttle to 3300 engine rpm at no
load
Worn engine governor
Replace or service engine governor