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23
Maintenance
PROBLEM
POSSIBLE CAUSE
SOLUTION
BURNER WILL
NOT LIGHT
(continued from
previous page)
Flex coupling slipping on fuel
pump shaft or burner motor shaft
Replace if needed.
On-Off switch defective
Check for electrical current reaching burner assembly
with burner switch on.
Heavy sooting on coil and burner
can cause interruption of air flow
and shorting of electrodes
Clean as required.
Improper electrode setting
Check and reset according to diagram in Operator's
Manual.
Fuel not reaching combustion
chamber
Check fuel pump for proper flow.
Check solenoid flow switch on machines with spray
gun control, for proper on-off fuel flow control.
Clogged burner nozzle
Clean as required.
Thermostat faulty or slow engine
speed
Increase engine RPM to increase voltage.
Flow switch malfunction
Remove, test for continuity and replace as needed.
Flow solenoid malfunction
Replace if needed.
FLUCTUATING
PRESSURE
Valves worn
Check and replace if necessary.
Blockage in valve
Check and replace if necessary.
Pump sucking air
Check water supply and air seepage at joints in suction
line.
Worn piston packing
Check and replace if necessary.
Gasoline engine altitude
The gasoline engine is preset for operation at altitudes
below 1000 ft above sea level.
If operated at higher altitudes, it may be necessary to
install a high altitude main jet in the carburetor. Contact
your local authorized engine sales and service center
for details.
MACHINE
SMOKES
WHILE
BURNER UNIT
IS RUNNING
OR
UNIT SMOKES AT
COLD-START
ONLY WHEN
BURNER
IS OFF
Improper fuel or water in fuel
Drain tank and replace contaminated fuel
Improper air adjustment
Readjust air bands on burner assembly
Fuel pressure is low <140 psi for
burner
Adjust fuel pump pressure to specifications
Burner nozzle is plugged or dirty
Replace nozzle. Check parts breakdown
for nozzle size
Burner nozzle spray pattern is
faulty
Replace nozzle. Check parts breakdown
for nozzle size
Heavy accumulation of soot on
coils and burner assembly
Remove coils and burner assembly,
clean thoroughly Call local dealer
Misaligned electrode setting
Realign electrodes to specifications
Obstruction in smoke stack
Check for insulation blockage or other
foreign objects
Low engine RPM
Increase RPM to correct specs. See serial plate
Fuel Pressure is too high for clean
burn (fuel PSI above 140 and below
200) and smokes when burner is off
Reduce fuel pressure PSI/Increase air band set for
cleaner without max water heat loss
9.808-341.0 - E - Operator's Manual, LFT