6 308864
PROBLEM CAUSE SOLUTION
Pump output low
Strainer (31) clogged Clean.
Piston ball (25) not seating Service piston ball check. Manual 308798.
Piston packings worn or damaged Replace packings. Manual 308798.
O-ring (227) in displacement pump is worn or
damaged
Replace o-ring. Manual 308798.
Intake valve ball not seating properly Clean and service. Manual 308798.
Engine speed is too low Increase throttle setting. See Manual 308863.
V–belt slipping Tighten V–belt with clamp (101). Adjust clamp
until it takes 15 lb of force to lock clamp down.
Clutch worn or damaged Replace. See page 9.
Pressure setting is too low Increase pressure. Manual 308863.
Fluid filter (318), tip filter or tip is clogged or
dirty
Clean filter. Manual 308863 or 309091.
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 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 worn or damaged Replace packings. Manual 308798.
Displacement rod worn or damaged Replace rod. Manual 308798.
Spitting from gun Air in fluid pump or hose Check for loose connections at pump intake
and tighten. Then prime pump. See Startup,
Manual 308863.
Tip partially clogged Clear.
Fluid supply is low or empty Refill and prime pump. See Startup, Manual
308863. Check fluid supply often to prevent
running pump dry.
Pump is difficult to prime Air leak Check all hose connections and tighten as
needed.
Reduce engine speed and cycle pump as
slowly as possible during priming.
Intake valve is leaking Shut off pump and relieve pressure. Disas-
semble and clean intake valve. Be sure ball
seat is not nicked or worn and that ball seats
well. Reassemble.
Worn packings Repack pump. Manual 308798.
Fluid is too thick Thin fluid according to supplier’s recommenda-
tions.
Engine speed is too high Decrease throttle setting before priming pump.
Manual 308863.
High engine speed at no
load
Misadjusted throttle setting. Reset engine throttle to 3600 – 3800 rpm at no
load
Worn engine governor Replace or service engine governor
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