Tecumseh HM70 User Manual

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GOVERNOR GEAR AND SHAFT SERVICE................................................................................................. 28
SPEED CONTROLS AND LINKAGE ............................................................................................................ 29
CHAPTER 5 REWIND STARTERS............................................................................................................... 35
GENERAL INFORMATION ............................................................................................................................ 35
OPERATION .................................................................................................................................................. 35
COMPONENTS ............................................................................................................................................. 35
SERVICE ....................................................................................................................................................... 35
ROPE SERVICE ............................................................................................................................................ 35
RETAINER REPLACEMENT ......................................................................................................................... 36
STYLIZED REWIND STARTER (TVS, HM, TVM, TVXL), AND STAMPED STEEL STARTER
(HM, VM, TVM, TVXL).............................................................................................................................. 36
STYLIZED REWIND STARTER WITH PLASTIC RETAINER ....................................................................... 37
STANDARD STAMPED STEEL AND CAST ALUMINUM STARTER (HM, VM) ........................................... 38
VERTICAL PULL STARTER HORIZONTAL ENGAGEMENT TYPE ............................................................. 39
VERTICAL PULL STARTER VERTICAL ENGAGEMENT TYPE................................................................... 40
CHAPTER 6 ELECTRICAL SYSTEMS ...................................................................................................... 42
GENERAL INFORMATION ............................................................................................................................ 42
OPERATION .................................................................................................................................................. 42
STARTING CIRCUIT AND ELECTRIC STARTERS ...................................................................................... 42
CHARGING CIRCUIT .................................................................................................................................... 42
CONVERTING ALTERNATING CURRENT TO DIRECT CURRENT............................................................ 43
HALF WAVE RECTIFIER SINGLE DIODE.................................................................................................... 43
FULL WAVE RECTIFIER BRIDGE RECTIFIER ............................................................................................ 43
COMPONENTS ............................................................................................................................................. 43
BATTERY....................................................................................................................................................... 43
WIRING.......................................................................................................................................................... 43
ELECTRICAL TERMS ................................................................................................................................... 44
BASIC CHECKS ............................................................................................................................................ 45
TROUBLESHOOTING ELECTRICAL STARTER CIRCUIT FLOW CHART.................................................. 46
TROUBLESHOOTING ELECTRICAL CHARGING CIRCUIT FLOW CHART............................................... 47
TESTING PROCEDURE ............................................................................................................................... 48
STARTING CIRCUIT...................................................................................................................................... 48
CHARGING CIRCUIT .................................................................................................................................... 48
VOLTAGE REGULATIONS ............................................................................................................................ 56
LOW OIL SHUTDOWN SWITCHES.............................................................................................................. 56
SERVICE ....................................................................................................................................................... 57
12 VOLT OR 120 VOLT ELECTRIC STARTERS WITH EXPOSED SHAFT................................................. 57
12 VOLT D.C. OR 120 VOLT A.C. ELECTRIC STARTERS WITH THE STARTER GEAR UNDER
THE CAP ASSEMBLY .............................................................................................................................. 57
INSPECTION ................................................................................................................................................. 58
CHAPTER 7 FLYWHEEL BRAKE SYSTEMS .............................................................................................. 59
GENERAL INFORMATION ............................................................................................................................ 59
OPERATION .................................................................................................................................................. 59
BOTTOM SURFACE SYSTEM...................................................................................................................... 59
INSIDE EDGE SYSTEM ................................................................................................................................ 60
COMPONENTS ............................................................................................................................................. 60
SERVICE ....................................................................................................................................................... 61
FLYWHEEL REMOVAL.................................................................................................................................. 61
BRAKE LEVER AND PAD ............................................................................................................................. 61
IGNITION GOUNDOUT TERMINAL.............................................................................................................. 61
STARTER INTERLOCK SWITCH.................................................................................................................. 62
CONTROL CABLE......................................................................................................................................... 62
BRAKE BRACKET REPLACEMENT............................................................................................................. 62
CHAPTER 8 IGNITION.................................................................................................................................. 63
GENERAL INFORMATION ............................................................................................................................ 63
OPERATION .................................................................................................................................................. 63
SOLID STATE IGNITION SYSTEM (CDI) ..................................................................................................... 63
MAGNETO IGNITION SYSTEM (POINTS) ................................................................................................... 63
IDENTIFICATION OF TECUMSEH IGNITION SYSTEMS ............................................................................ 64
COMPONENTS ............................................................................................................................................. 64
IGNITION TROUBLESHOOTING.................................................................................................................. 66

Tecumseh HM70 Specifications

General

Brand	Tecumseh
Model	HM70
Category	Engine
Language	English