TM-9-2320-387-24 HMMWV Direct Support & General Support Maintenance Manual Volume 1 Download

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TM 9-2320-387-24-l DIAGNOSTIC FLOWCHART r OPTIONS DOES THE EXHAUST SMELL LIKE RAW FUEL? PUT A PIECE OF PAPER IN THE EXHAUST STREAM THEN LOOK AT AND SMELL IT FOR SIGNS OF UNBURNT FUEL. I REASON FOR QUESTION White smoke indicates fuel not being burned in the cylinders, or possible loss of coolant to the exhaust. FUEL SYSTEM KNOWN INFO I WHITE SMOKE INTERNAL ENGINE PROBLEMS FUEL QUALITY r KNOWN INFO TEST OPTIONS VISUAL WHITE SMOKE DOES THE EXHAUST SMOKE FOR MORE THAN 2 OR 3 MINUTES AFTER STARTING THE ENGINE? REASON FOR QUESTtON Some white smoke after a cold start is normal. The colder it is, the more white smoke you’ll see. The glow plugs keep cycling after the engine starts which will reduce this smoking. If you think that there is too much smoke after a cold start, run the glow plugs circuit tests (page 2-299) paying special attention to the afterglow operation. POSSIBLE PROBLEMS INJECTION TIMING INTERNAL ENGINE PROBLEMS FUEL QUALITY RETURN CHECK VALVE KNOWN INFO ST OPTIONS GLOW PLUGS CIRCUIT TESTS (Page 2-289) GLOW PLUGS OK WHITE SMOKE RUN THE GLOW PLUGS CIRCUIT TESTS. IF NO FAULTS FOUND, NOTIFY OS MAINTENANCE (CHAPTER 14). POSSIBLE PROBLEMS REASON FOR QUESTION If the glow plugs are not functioning properly, the cylinders will not warm up as rapidly as they should. ENGINE MECHANICAL 2-126