21. Ignition Switch
a. Location. The ignition switch (8, fig. 11) is located in the lower right corner of the instrument panel (3).
b. Purpose. The ignition switch is used to open and close the electrical circuit of the engine.
22. Oil Pressure Gage
a. Location. The oil pressure gage (5, fig. 11) is located on the top of the cluster gage.
b. Purpose. The oil pressure gage indicates the pressure at which the oil is being supplied to the engine. At normal
operating speeds, the pressure must range between 20 and 50 pounds.
Note. When the oil pressure is less than 10 pounds, or more than 50 pounds, stop the engine and determine the
cause of the low or high reading.
a. Location. The battery charging ammeter (9, fig. 11) is located on the right side of the cluster gage.
b. Purpose. The battery charging ammeter shows the amount of electricity flowing into the battery or out of the
battery. If the electrical units of the engine require more electricity than the generator is producing, the indicating hand of
the ammeter will be on the minus side of the ammeter and show a discharge of the battery. If the output of the generator
is greater than the electricity required, the indicating hand will be on the plus side of the ammeter and show charge. With
the engine running at normal operating speeds, the battery charging ammeter should approach zero or show just a slight
Note. If the ammeter shows a continuous low or high charge, stop the engine and determine the cause of
the low or high readings.
24. Temperature Gage
a. Location. The temperature gage (10, fig. 11) is located on the bottom of the cluster gage.
b. Purpose. The temperature gage indicates the temperature of the coolant in the cylinder block. The normal
temperature reading is between 130° and 190° F. Readings above or below this range indicate trouble in the cooling or
Note. When the engine overheats, or Is continuously overcooled, stop the engine and determine and
correct the trouble.
25. Fuel Gage
a. Location. The fuel gage (4, fig. 11) is located on the left side of the cluster gage.
b. Purpose. The fuel gage indicates the amount of fuel in the fuel tank.