When you have started the engine, let it run for 20 to 30 seconds before you put a load on the engine. But do not leave the vehicle while the engine is running.
Avoid unnecessary idling of diesel engine equipped vehicles.
If the engine idles too long, the temperature of the engine coolant will fall below the normal operating range. Low engine operating temperature causes several conditions which affect engine operation and reduce engine life.
The engine should be permitted to go through a warm-up period. Operate the vehicle at a minimum of 600 rpm during the warm-up period. During this period and during operation, the following observations should be made.
During this warm-up period, check the warning lights and gages:
| • | If oil pressure does not begin to rise within 15 seconds of starting, stop the engine and find the cause. See Oil Pressure Gage for more information. |
| • | If the engine coolant temperature gage needle goes into the hot area on the gage, stop the engine and find the cause of the overheating. See Engine Coolant Temperature Gage for more information. |
| • | If you have air brakes, the dual-needle air pressure gage should read at least 115 psi (790 kPa) for both service systems before you try to move the vehicle. When air pressure is below 60 psi (420 kPa), the LOW AIR light will come on and you will hear a tone alarm. See Brake System Warning Light for more information. If the pressure does not build up or drops during warm-up, stop the engine and find the cause before you try to move the vehicle. Recommended air pressure before driving is 120 psi (830 kPa). See Air Pressure Gage for more information. |
| • | The charging system light should come on when the ignition key is turned to ON/RUN or START and should go out when the engine is running above idle. If the light does not go out or comes back on during normal engine operation, have the charging system checked right away. (This light tells you if the generator is not charging; it does not reflect the condition of the battery.) See Charging System Light for more information. |
| • | The voltmeter charge indicator gage tells you the condition of the battery's charge. The gage should be in the center area during engine operation. The red area on the left indicates an undercharge condition; the red area on the right indicates an overcharge. If the gage is in either red area, have the battery and charging system checked right away. See Voltmeter Gage for more information. |
Notice: Do not allow the engine to operate at low idle for more than five minutes. This can cause low engine operating temperatures which can affect engine operation and reduce engine life. Engine idle speed should be increased to 1200 rpm whenever extended idle is required. Once started, the engine should be placed under load to allow the engine coolant temperature to reach 150°F (66°C) before shutting off the engine.
