Figure 12-29. - Operating Instruction plate.

1. Open the service valves about one quarter-not wide open.

NOTE: The reason for starting with the service valves partly open is that they aid in quicker warm-up of the compressor oil.

2. Position the low-pressure, engine-oil-system safety knob to ON (fig. 12-30).

3. Turn the ignition switch to the START position. Immediately after the engine starts, release the ignition switch. If the engine fails to fire within 30 seconds, release the ignition switch and allow the starting motor to cool off for a few moments before trying the starter again.

4. With the engine running, check the engine oil pressure gauge. If no pressure is indicated, turn the engine off. When the oil pressure goes above 22 psi, continue to operate the engine and check the low-pressure engine oil switch. The knob on this switch should be in the RUN position.

NOTE: The engine oil pressure gauge indicates erratically until the engine oil warms up.

5. Open the side curtains on both sides of the engine enclosure and leave them open. The flow of air through the oil cooler and engine radiator will be impeded if the side curtains are closed while the engine is running.

6. After the engine has run about 3 minutes, check the engine coolant temperature gauge. The gauge should indicate less than 210°F. If the gauge is showing more than 210°F, SHUT OFF THE ENGINE.

Figure 12-30. - Instrument panel.