The Design and Development of the L-Series Small Air-Cooled Diesel Engine

THIS PAPER DESCRIBES THE FEATURES OF THE VERTICAL, SINGLE-CYLINDER AIR-COOLED DIRECT INJECTION DIESEL ENGINE (MODEL L), FOCUSING ON THE TECHNOLOGY USED TO MINIMIZE ITS SIZE AND WEIGHT. THE L-SERIES ENGINES ARE EXTREMELY COMPACT AND LIGHT WEIGHT DIESELS WITH EXCELLENT FUEL ECONOMY AND DURABILITY. THEY ARE USED IN MANY TYPES OF SMALL INDUSTRIAL AND AGRICULTURAL EQUIPMENT FOR WHICH AIR-COOLED GASOLINE ENGINES HAVE HITHERTO BEEN THE NORM.

ONE OF THE MOST NOTABLE DESIGN FEATURES IS THE USE OF DIRECT INJECTION TECHNOLOGY FOR SMALL, HIGH-SPEED ENGINES. THIS NECESSITATED THE USE OF AN ULTRA-SMALL DESIGN FOR THE FUEL INJECTION EQUIPMENT. A SECOND FEATURE IS THE SIDE LID (CRANKCASE) CONSTRUCTION WHICH IS HERE ADOPTED FOR USE IN THE DIESEL ENGINE FOR THE FIRST TIME. THIS HAS BEEN INSTRUMENTAL IN REDUCING THE SIZE, WEIGHT AND PRODUCTION COST. A THIRD FEATURE IS THE RECOIL STARTER UNIT, WHICH IS STANDARD EQUIPMENT. THE STARTER ENSURES EASIER AND CHEAPER OPERATION THAN IS POSSIBLE WITH THE NORMAL HANDLE OR ELECTRIC-STARTER UNIT.

THE ENGINE DESIGN ALSO REDUCES NOISE LEVELS BY 5 TO 6 DB(A) COMPARED WITH CONVENTIONAL DIESEL ENGINES, MAKING THE ENGINE MORE PLEASANT TO USE.