105644-0290 ZEXEL 9 420 615 689 BOSCH AUTOM. ADVANCE MECHANISM 9420615689 1056440290 1157402040

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 using fuel according to recommendations by Caterpillar.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 35 kPa (5 psi) of air pressure to the fuel tank.
Do not use more than 55 kPa (8 psi) of air pressure in the fuel tank or damage to the tank may result.
Check for leakage at the connections between the fuel tank and the fuel transfer pump. If leaks are found, tighten the connections or replace the lines. If there are no visual leaks, remove the fuel supply line from the tank and connect it to an outside fuel supply. If this corrects the problem, 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 of this Service Manual.6. Automatic Timing Advance Does Not Operate Correctly ... Check with engine warm. Use the 8T5300 Timing Indicator Group to check the automatic timing advance unit. Check to see that the advance is smooth and that the amount of advance is correct. See Fuel System of the Testing and Adjusting section of this Service Manual for the subject Checking Engine Timing And Automatic Timing Advance Unit With 8T5300 Timing Indicator Group. If the timing indicator is not available, make rapid "acceleration" (increase in speed) from low idle to high idle. Engine must have smooth acceleration. A timing advance that does not operate correctly