35. ENGINE OIL PAN HEATER, COOLANT HEATER 35.2PRECAUTIONS WHEN USING 1. This heater is used for maintaining the temperature. If the engine has cooled completely, it will take an extremely long time to warm up the engine. In such cases, do as follows. If the machine has cooled to the ambient temperature, it is necessary to use the electric heater (engine) and a fan heater (to warm the inside of the engine room) before starting the engine. The relationship between the ambient temperature and the heater device and time taken to warm up the engine until the engine can be started again is shown in graph B. Please use this graph for reference.
Graph B gives the general situation, so adjust the values to match the actual working conditions of the machine. (Note that the items marked with fl must not be adjusted.) Example of using graph B When ambient temperature is –40°C and engine oil is SAE15W-40 Start the electric heater 6.5 hours before starting the engine. This makes it possible for the engine to be started. NOTICE Be sure to turn off the heater before starting the engine. Do not attempt to start the engine under any circumstances before the heater has been used for at least 4 hours (fl mark in graph B). If a fan heater is also used, it is possible to reduce the warming-up time.
If a fan heater is used, cover the rear of the engine with canvas. The curve for the fan heater shown in graph B is the curve when using a 88,000 kcal/h jet heater. When ambient temperature is –50°C and engine oil is SAE15W-40 Start the electric heater 4 hours before starting the engine and use a fan heater (88,000 kcal/h) in the engine room at the same time. This makes it possible for the engine to be started. NOTICE It is difficult to start the engine using only the electric heater. Do not attempt to start the engine under any circumstances before the electric heater and fan heater (88,000 kcal/h) have been used for at least 2.5 hours (fl mark in graph B). 2.
Always be sure to turn the electric heater off before starting the engine. If the engine is started with the electric heater still switched on, the following troubles will occur. When the filament of the electric heater is at a high temperature, the high-temperature strength of the filament is reduced, and vibration caused by starting the engine may cause the filament to break because of fatigue. If the electric heater is switched on when the engine is running, the heat of the engine itself will be added to the heat from the heater, and this will cause overheating of the coolant and lubricating oil.
CAUTION When the filament of the electric heater is at a high temperature, the high-temperature strength of the filament is reduced, and vibration caused by starting the engine may cause the filament to break because of fatigue. 3. Do not use the heater when the ambient temperature is more than 5°C. If heater is used when the ambient temperature is more than 5°C, it will cause deterioration of the lubricating oil. 4. If air is trapped in the engine cooling water circuit, the circulation of the heated water will be poor and the heat maintenance effect will be reduced.
If the cooling water has been changed or it is thought that there is air trapped in the water circuit, crank the engine to bleed the air. 5. When using the electric heater, always make sure that the power supply is properly grounded. 5-52