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Troubleshooting
8
312195B
Pump output is low.
Strainer (34f) is clogged.
Clean strainer.
Piston ball is not seating.
Service piston ball. See pump manual.
Piston packings are worn or damaged.
Replace packings. See pump manual.
O-ring in pump is worn or damaged.
Replace o-ring. See pump manual.
Intake valve ball is not seating properly.
Clean intake valve. See pump manual.
Intake valve ball is packed with material.
Clean intake valve. See pump manual.
Engine speed is too low.
Increase throttle setting. See operation manual.
Clutch is worn or damaged.
Replace clutch. Page 13.
Pressure setting is too low.
Increase pressure. See operation manual.
Fluid filter (11), tip filter or tip is clogged or dirty.
Clean filter. See operation or spray gun manual.
Large pressure drop in hose with heavy materi-
als.
Use larger diameter hose and/or reduce overall
length of hose. Use of more than 100 ft of 1/4 in.
hose significantly 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. See pump manual.
Displacement rod is worn or damaged.
Replace rod. See pump manual.
Fluid is spitting from gun. Air in pump or hose.
Check and tighten all fluid connections. Reprime
pump. See operation manual.
Tip is partially clogged.
Clear tip. See spray gun manual.
Fluid supply is low or empty.
Refill fluid supply. Prime pump. See operation
manual. Check fluid supply often to prevent run-
ning 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. See pump manual.
Paint is too thick.
Thin the paint according to the supplier's recom-
mendations.
Engine speed is too high.
Decrease throttle setting before priming pump.
See operation manual.
Problem
Cause
Solution
Summary of Contents for LineLazer IV 3900
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