PROBLEM
Displacement pump oper-
ates, but output is low on up-
stroke
Displacement pump oper-
ates but output is low on
downstroke and/or on both
strokes
Pump is difficult to prime
High engine speed at no
load
Low stall or run pressure
shown on display
10
309896
Troubleshooting
CAUSE
Piston ball (206) is not seating
Piston packings are worn or damaged
Strainer (31) is clogged
O-ring (227) in pump is worn or damaged
Intake valve ball is packed with material or is
not seating properly
Engine speed is too low
Suction tube air leak
Pressure setting is too low
Fluid filter (203), tip filter or tip is clogged or
dirty
Large pressure drop in hose with heavy
materials
Air in pump or hose
Intake valve is leaking
Pump packings are worn
Paint is too thick
Engine speed is too high
Misadjusted throttle setting
Worn engine governor
New pump or new packings
Faulty transducer
SOLUTION
Service piston ball. Manual 309277.
Replace packings. Manual 309277.
Clean strainer. Sprayer 233716 strainer is for
use in paint only.
Replace o-ring. Manual 309277.
Clean intake valve. Manual 309277.
Increase throttle setting. Manual 309892.
Tighten suction tube.
Increase pressure. Manual 309892.
Clean filter. Manual 309892 or 309741.
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).
Check and tighten all fluid connections.
Reduce engine speed and cycle pump as
slowly as possible during priming.
Clean intake valve. Be sure ball seat is not
nicked or worn and that ball seats well. Reas-
semble valve.
Replace pump packings. Manual 309277.
Thin the paint according to the supplier's
recommendations
Decrease throttle setting before priming pump.
Manual 309892.
Reset throttle to 3700 – 3800 engine rpm at no
load
Replace or service engine governor
Pump break-in period takes up to 100 gallons
of material
Replace transducer