Curtis Dyna-Fog BLACKHAWK 2620, Instruction Manual

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ADJUSTING THE FUEL NEEDLE
The engine must be running in order to adjust the Fuel Needle.
If the engine will not run and the Fuel Needle is set between 1⁄2 - 1 turn out, the Fuel Needle setting
is not likely to be the problem.
If the engine will not run and the Fuel Needle is not set between 1⁄2 - 1 turn out, set the Needle to this
setting. The machine should start in this range.
Once the machine is running, proceed as follows:
1. With water or Flushing Solution in the Formulation Tank, move the machine where it can
be fogged briefly with safety.
2. Start the machine and pull open the automatic-shutoff-valve stem. (Model 2620 only)
CAUTION
If the machine is running too lean or too rich, the next step may cause the engine to
stop and a small amount of flame may exit the engine discharge.
NOTE
A Pulse Jet Engine which has lean fuel-air mixture will not carry fog. A Pulse Jet Engine, if
running rich will run rough or sputter frequently.
WARNING
WHEN ADJUSTING THE FUEL NEEDLE DO NOT TOUCH THE ENGINE HOUSING. THE
HOUSING HEATS UP QUICKLY TO A TEMPERATURE WHICH CAN CAUSE SERIOUS
BURNS IF TOUCHED.
3. Using a small regular tip screwdriver, slowly rotate the Fuel Needle clockwise, then
counter-clockwise. Listen to the sound of the engine and adjust the Carburetor Fuel
Needle to the setting where the engine is running smoothest and strongest. This setting
should be the correct Fuel Needle setting.
4. Rotate the 3-way selector valve to the fog position.
5. If the engine stops or hesitates, immediately rotate the valve lever to the purge position
and adjust the Fuel Needle counter-clockwise 1/16
th
turn or less. Repeat steps 4 and 5
until the engine no longer hesitates or stops when beginning to fog.
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