Engine Operation- 4.5 L Engines Warming Engine IMPORTANT: To assure proper lubrication, operate engine at or below 1200 rpm with no load for minutes. Extend this period minutes when operating at temperatures below freezing. RG6574 –UN–17FEB03 Engines used in generator set applications where the governor is locked at a specified speed may not have a slow idle function. Operate these engines at high idle for 1 to 2 minutes before applying the load. This procedure does not apply to standby generator sets where the engine is loaded immediately upon reaching rated speed. Oil Pressure and Coolant Temperature Gauges (Earlier Engines) RG13361 –UN–06FEB04 1.
Check oil pressure gauge (A) as soon as engine starts. If gauge needle does not rise above minimum oil pressure specification of 105 kPa (1.05 bar) (15.0 psi) within 5 seconds, stop the engine and determine the cause. Normal engine oil pressure is 345 ± 103 kPa (3.45 ± 1.03 bar) (50 ± 15 psi) at rated full load speed (1800–2500 rpm) with oil at normal operating temperature of 115 ° C (240 ° F). This oil pressure can vary from 35 psi to 65 psi. Oil Pressure and Coolant Temperature Gauges (Later Engines) A—Oil Pressure Gauge B—Coolant Temperature Gauge NOTE: On certain engines, the oil pressure and coolant temperature gauges are replaced by indicator warning lights.
The lights must be "OFF" when engine is running. 2. Watch coolant temperature gauge (B). Do not place engine under full load until it is properly warmed up. The normal engine coolant temperature range is 90 ° 100 ° C (194 ° –212 ° F). NOTE: It is a good practice to operate the engine under a lighter load and at lower speeds than normal for the first few minutes after start-up. OURGP11,000014D –19–06JAN04–1/1 20-8 021604 PN=123