STARTING
A choke button is provided on the instrument board to assist in starting. Pulling out this button closes a butterfly choker valve (see cut) in the air intake passage of carbureter which restricts the air opening of the carbureter, and consequently produces a richer mixture.
To start engine, pull out choke button all the way. Advance spark lever about half way and throttle lever about one-quarter way and depress starter pedal.
As soon as motor fires when starting, this control should be released part way, otherwise too much fuel will be drawn from carbureter, causing flooding of the motor and failure of the latter to continue to promptly fire. After starting, motor should be allowed to run "part choke" as stated for a few minutes while warming up, then the choker control should be fully released, or pushed in completely on the instrument board, and engine allowed to run normally for sometime until water in cylinder jackets is thoroughly warmed up before starting to make final carbureter adjustments.
HEAT CONTROL—STOVE
In the colder seasons warm air is fed to air intake of carbureter through the warm air elbow "F" (see cut). This elbow connects the carbureter with the warm air stove, which is a casting surrounding the two exhaust heat tubes which supply exhaust heat to the carbureter jackets as described below.
The amount of heat required for proper carburation depends on the temperature of the outside air. The first means of control is in the warm air stove just described, which should be connected to the carbureter furnishing warm air to carbureter air intake in all seasons of the year when the outside air temperature is below 50° F., whenever the outside air temperature runs above this point cold air should be furnished to carbureter air intake. This can be done by loosening the wing nut holding the warm air elbow "F" on the stove and also loosening the set screw holding this elbow in the air intake of carbureter, after which slide elbow out of air intake and revolve it—180 degrees about an horizontal axis and re-insert in carbureter air intake and lock in place with set screw. The opening in the elbow now is turned down away from the stove and draws in only cold air.
The above procedure, it must be understood, will vary somewhat due to differences in locality, altitude and fuels used, but it should be borne in mind that the best economy can be had with cold air passing to the carbureter, and the stove should not be connected until the acceleration and performance of the job requires the use of warm air for the best results.
The adjustment of the carbureter should be made per the above description of the stove, as the latter is used for meeting weather conditions and should be set as described.