Step 3. When smoke turns pale blue, close the float bowl toggle valve (3).
Step 4. Pump the magneto air pump handle (4) about 15 times after the engine stops to purge hot gases
from the engine. Repeat if the engine fires during pumping.
Step 5. Close the fuel line shutoff valve (5).
Step 6. Press the relief valve (6) at each end of the fog oil pump and drain the oil.
After-operation Services
After-operation services that the operator will perform on the M3A4 smoke generator are as
follows:
Fog Oil System. Inspect the fog oil inlet and exhaust hoses for condition. Failure to keep fog oil
hoses from contacting generator components that become extremely hot will cause charring and rapid
deterioration. Inspect the fog oil sediment strainer and clean if necessary. Check the operation and
position of the oil-metering globe valve.
Fog Oil Pump Assembly. Inspect and tighten the fog oil line and the pressurizing-line connections
as required. Inspect the general condition of the pump and the operation of the drain cock.
Starting System. Inspect the air pump for operation and see that it is secure. Inspect the magneto-
air pump and the spark igniter to make certain that the components are secure.
Frame Assembly. Inspect the frame and fittings for dents, cracks, and loose bolts. Clean and
tighten as required. Check the toolbox for tools, repair parts, and accessories to ascertain that they are
present and in good condition.
Cleaning Equipment. Clean the engine head assembly and replace the engine valve if necessary.
Clean the fog oil pump and all metal surfaces of the smoke generator with dry cleaning solvent.
Remove the fog oil inlet hose from the drum. Drain the oil from the hose and wipe the exterior dry.
Stow the fog oil inlet hose on the smoke generator. Remove the fog oil exhaust hose from the drum, and
wipe the exterior dry. Stow the exhaust hose on the smoke generator. Replace the bungs in the fog oil
drum and tighten with the bung wrench.
Learning Event 4
IDENTIFY PROCEDURES FOR OPERATING THE M3A4 SMOKE GENERATOR UNDER
UNUSUAL CONDITIONS
The operation of the M3A4 smoke generator will not always be carried on under ideal conditions. You
may have to make smoke in extreme cold or extreme heat. Some effects of unusual weather on
operations are rain, mud, dust, sleet, snow, and ice can clog parts and contaminate fuel or fog oil
supplies. In hot weather, gasoline evaporates quickly when gas caps and the fuel tank cap are not
secured tightly. In freezing weather (below 32F and 0C) fog
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