QP4TH TRASH PUMP • OPERATION AND PARTS MANUAL — REV. #3 (01/29/14) — PAGE 27
Table 7. Engine Troubleshooting
Symptom
Possible Problem
Solution
Operation not satisfactory
Rotational speed fluctuates.
Governor adjustment improper?
Adjust governor to correct lever.
Governor spring defective?
Clean or replace ignition.
Fuel flow erratic?
Check fuel line.
Air taken in through suction line?
Check suction line.
Recoil starter not working properly.
Dust in rotating part?
Clean recoil starter assembly.
Spring failure?
Replace spiral spring.
TROUBLESHOOTING (ENGINE/PUMP)
Table 8. Pump Troubleshooting
Symptom
Possible Problem
Solution
Pump does not take
on water.
Not enough priming water in the housing?
Add water.
Engine speed too low?
Increase throttle.
Strainer plugged?
Clean strainer.
Suction hose damaged?
Replace or repair hose, and clamps.
Air leak at suction port?
Check that fittings are tight and properly
sealed.
Pump is located too high above water line? Move pump closer to water.
Debris collecting in pump housing?
Clean pump housing.
Too much distance between impeller
and volute.
Adjust clearance by adding shims or
replace impeller. Min. .006" - Max. .020".
Water leaking out weep hole between pump
and engine?
Check condition of mechanical seal and
gaskets, between pump end and engine
housing.
Pump takes in water, little or
no discharge.
Engine speed too low?
Increase throttle speed.
Suction strainer partially plugged?
Clean strainer.
Impeller/Volute worn?
Adjust clearance by adding shims or
replace impeller/volute.
Suction hose leaks at inlet.
Fittings/clamps are not sealed properly?
Tighten, replace or add clamp. (Keep
extra seals on pump).
Hose diameter is too large?
Use smaller diameter hose or replace
hose.
Discharge does not stay on
coupling.
Pressure too high?
Check pressure, add additional clamp.
Hose kinked or end blocked?
Check hose.
Impeller does not turn:
pump is hard to start.
Impeller jammed or blocked?
Open pump cover and clean dirt and
debris from inside housing.
Impeller and volute binding?
Adjust clearance by removing shim from
behind impeller.
Defective engine?
See Engine Owner's Manual.
Summary of Contents for QP4TH
Page 2: ...PAGE 2 QP4THTRASH PUMP OPERATION AND PARTS MANUAL REV 3 01 29 14 PROPOSITION 65 WARNING...
Page 3: ...QP4THTRASH PUMP OPERATION AND PARTS MANUAL REV 3 01 29 14 PAGE 3 NOTES...
Page 30: ...PAGE 30 QP4THTRASH PUMP OPERATION AND PARTS MANUAL REV 3 01 29 14 PUMP ASSEMBLY...
Page 32: ...PAGE 32 QP4THTRASH PUMP OPERATION AND PARTS MANUAL REV 3 01 29 14 PUMP ASSEMBLY...
Page 34: ...PAGE 34 QP4THTRASH PUMP OPERATION AND PARTS MANUAL REV 3 01 29 14 ENGINE SERVICE PARTS...
Page 37: ...QP4THTRASH PUMP OPERATION AND PARTS MANUAL REV 3 01 29 14 PAGE 37 NOTES...
