SPRING-FUEL RATIO CONTROL 1245657 - Caterpillar

3208 Engines In All ApplicationsSUPPLEMENT: 02/11/85SERVICE MAGAZINE, MARCH 5, 1984, PAGE 5. In the article, "Causes Of White Exhaust Smoke During Cold Weather Starts And Ways To Reduce It", put a mark though the paragraph that follows Step 3.The correct new paragraph follows. A starting aid can also help reduce the amount and duration of white smoke. The 9N5753 Jacket Water Heater Group has two 750 watt, 120 volt heater elements, one for each side of the engine block. The jacket water heater increases the coolant temperature in the cylinder block. Increased coolant temperature increases the temperature in the cylinder at the time of compression. This causes the fuel to burn more completely. Special Instruction, Form SEHS7299 has installation instructions. It is included in the group. The 9N5753 Jacket Water Heater Group consists of these parts:
--------------- END SUPPLEMENT ---------------SUPPLEMENT: 04/02/84SERVICE MAGAZINE, MARCH 5, 1984, PAGE 4. In the article, "Causes Of White Exhaust Smoke During Cold Weather Starts And Ways To Reduce It", the first line of the chart on the top of page 5 should be changed.Change the Amount of Fuel column to read "1512 liters (400 gal)."--------------- END SUPPLEMENT ---------------Extremely cold temperatures can affect engine performance. In cold weather, starting an engine will probably cause some white smoke and initial rough running characteristics. These characteristics don't always mean there is a problem, but pay careful attention to the amount and duration of the smoke. There is a fine line between the amount of smoke that is normal and smoke that may indicate a problem.
White exhaust smoke is made up of fuel vapors and aldehydes created by incomplete engine combustion. Ignition delay during cold weather is often the cause. There is not enough heat in the combustion chamber to ignite the fuel. Therefore, the fuel does not burn completely.
There are some temperature and engine speed limits which will help you determine if the white smoke produced by an engine is normal.
At an ambient and engine temperature of -9°C (15°F), white exhaust smoke may be visible for 8 to 16 minutes with the engine at 1400 rpm idle speed. Lower temperatures increase the amount and duration of the smoke. To decrease the duration, put a load on the engine. This raises engine temperature and aids combustion.
If the engine still is producing white smoke after 20 minutes with engine at 1400 rpm and the outside temperature at-9°C (15°F), it may indicate a problem.
To correct a white smoke problem, follow these steps:
1. Check the fuel quality, A.P.I. gravity and cetane number. Fuel suppliers should know the cetane number of their fuel. Use a light diesel fuel or kerosene with an A.P.I. gravity range of 41-44. The minimum cetane number for direct injection engines is 40. The correct fuel with these specifications will cause less white exhaust smoke, make it easier to start the engine and reduce rough running characteristics. Special Instruction, Form SEHS7067, has Caterpillar fuel recommendations.2. Check the fuel system timing. Make sure the timing is not retarded. Use