CHAPTER XII ENGINE MAINTENANCE Fuel system and carbureter—Carbureter adjustment—Dirt in the fuel—Running on kerosene—Care—Magneto and ignition system—Care of magneto—Smoothing platinum points—Adjustment—Timing a magneto—Testing a magneto—Ignition trouble—Compression—Testing for compression leaks—Valve grinding—Valve timing—Carbon—Removing carbon 213 CHAPTER XIII LOCATING TROUBLE Engine will not start—Engine loses power—Engine stops—Engine misses—Engine starts; but stops—Engine overheats—Engine smokes 245 CHAPTER XIV CAUSES OF TROUBLE Troubles and their causes in tabular form 259 INDEX 261 ILLUSTRATIONS FIG. PAGE 1 The Gas Engine Cycle 15 2 1-cylinder power diagram 21 3 2-cylinder power diagram 22 4 2-cylinder power diagram, 180 shaft 24 5 H. D. O. power diagram 26 6 4-cylinder power diagram 27 7 2-cylinder crank shaft 31 8 4-cylinder crank shaft 32 9 Half of a plain bearing 32 10 Connecting rod bearings 33 11 Piston complete and in section 34 12 Wrist pin fastenings 36 13 Valve 38 14 Action of cam 39 15 “Twin City” tractor engine 41 16 “Hart-Parr” valve mechanism 43 17 “Hart-Parr” engine 45 18 “Oil-Pull” engine 47 19 Horizontal double opposed engine 49 20 “Monarch” engine 51 21 Principle of carburetor 59 22 Principle of extra air inlet 64 23 “Kingston” carburetor, model L 72 24 “Kingston” carburetor, model E 75 25 “Kingston” carburetor, dual model 77 26 “E-B” carburetor 79 27 “E-B” carburetor, side view 81 28 Pump-fed carburetor 82 29 “Titan” carburetor 84 30 Pump-fed carburetor with two fuel nozzles 85 31 “Hart-Parr” mixture heater 87 32 “Twin City” manifold 88 33 Fuel pump 90 34 “Avery” fuel connections 92