CONTROL AS-RATIO 7W5634 - Caterpillar

White Smoke: Recommended Procedure
1. Cold Outside Temperatures - When the air outside is cold, the cylinder temperature is cooler. Not all the fuel will burn in the cylinders. The fuel which does not burn comes out the exhaust as white smoke. White smoke is normal in cold temperatures until the engine operates long enough to become warm. There will be less white smoke if No. 1 diesel fuel is used.2. Long Idle Periods - When an engine runs at idle speed for a long period of time, the cylinders cool and all of the fuel does not burn. Do not idle an engine for a long period of time. Stop an engine when it is not in use. If long idle periods are necessary use No. 1 diesel fuel.3. Low Quality Fuel - Test the engine with fuel according to recommendations by Caterpillar Tractor Co.4. Air in Fuel System - With air in the fuel system the engine will normally be difficult to start, run rough and release a large amount of white smoke. To remove the air from the fuel system open the manual bleed valve on the fuel injection pump housing. Operate the priming pump until the flow of fuel from the manual bleed valve is free of air. Close the manual bleed valve and fasten the fuel priming pump. Start the engine. If the engine still does not run smooth or releases a large amount of white smoke, loosen the fuel line nuts one at a time at the cylinder heads, and permit the fuel to come out until it is free of air. Tighten the fuel line nuts. If air is not removed in this way, put 5 psi (35 kPa) [CAUTION do not use more than 8 psi (55 kPa)] of air pressure to the fuel tank and check for leaks at connections between the fuel tank and the fuel transfer pump. If there are no leaks at the connections, remove the fuel supply line from the tank and connect it to an outside fuel supply. If this corrects the problem in the suction line (standpipe) inside the fuel tank has a leak.5. Fuel Injection Timing Not Correct - Check and make necessary adjustments as per Testing and Adjusting section