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CONTENTS
C Tecumseh Products Company
1998
Page
CHAPTER 1 GENERAL INFORMATION .......................
1
ENGINE IDENTIFICATION ............................................. 1
INTERPRETATION OF MODEL NUMBER ..................... 1
SHORT BLOCKS ............................................................. 2
FUELS ............................................................................. 2
ENGINE OIL .................................................................... 2
CAPACITIES .................................................................... 2
OIL CHANGE INTERVALS .............................................. 3
OIL CHECK ...................................................................... 3
OIL CHANGE PROCEDURE .......................................... 3
TUNE-UP PROCEDURE ................................................. 3
STORAGE ....................................................................... 4
DRAINING THE FUEL SYSTEM ..................................... 4
OIL CYLINDER BORE .................................................... 4
CHAPTER 2 AIR CLEANERS .......................................
5
GENERAL INFORMATION ............................................. 5
OPERATION .................................................................... 5
COMPONENTS ............................................................... 5
TROUBLESHOOTING OR TESTING ............................. 6
SERVICE ......................................................................... 6
DISASSEMBLY PROCEDURE ....................................... 6
POLYURETHANE-TYPE FILTER ELEMENT
OR PRE-CLEANER..................................................... 7
PAPER -TYPE FILTER ELEMENT ................................. 7
FLOCKED SCREEN ........................................................ 7
CHAPTER 3 CARBURETORS AND FUEL SYSTEMS .
8
GENERAL INFORMATION ............................................. 8
OPERATION .................................................................... 8
FUEL PRIMERS .............................................................. 9
IMPULSE FUEL PUMPS ................................................. 9
FLOAT STYLE CARBURETORS .................................... 9
CARBURETOR VISUAL IDENTIFICATION .................... 10
SERIES I CARBURETORS ............................................. 10
SERIES III & SERIES IV CARBURETORS .................... 10
SERIES VI CARBURETORS .......................................... 10
SERIES VII ...................................................................... 10
SERIES VIII ..................................................................... 11
SERIES IX ....................................................................... 11
WALBRO MODEL LMK ................................................... 11
TESTING ......................................................................... 12
SERVICE ......................................................................... 12
CARBURETOR PRE-SETS AND ADJUSTMENTS ........ 12
PRE-SETS AND ADJUSTMENTS
(TECUMSEH AND WALBRO CARBURETORS) ......... 13
FINAL ADJUSTMENTS ................................................... 13
TECUMSEH CARBURETORS ........................................ 13
WALBRO CARBURETOR ............................................... 13
CARBURETOR DISASSEMBLY PROCEDURE ............. 14
IMPULSE FUEL PUMP ................................................... 15
FLOAT ADJUSTING PROCEDURE ................................ 16
INSPECTION ................................................................... 16
THROTTLE AND CHOKE ............................................... 16
IDLE AND HIGH SPEED MIXTURE ADJUSTING
SCREW ........................................................................ 16
FUEL BOWL RETAINING NUT ....................................... 16
FUEL BOWL, FLOAT, NEEDLE AND SEAT ................... 17
ASSEMBLY PROCEDURE ............................................. 18
WELCH PLUGS ............................................................... 18
THROTTLE SHAFT AND PLATE .................................... 18
CHOKE SHAFT AND PLATE .......................................... 19
FUEL INLET FITTING ..................................................... 19
HIGH AND LOW SPEED ADJUSTING SCREW,
MAIN NOZZLE ............................................................. 19
INLET NEEDLE AND SEAT ............................................ 20
FLOAT INSTALLATION ................................................... 20
FUEL BOWL AND BOWL NUT ....................................... 21
IMPULSE FUEL PUMP ................................................... 21
PRIMER BULB ................................................................ 21
FINAL CHECKS ............................................................... 21
CHAPTER 4 GOVERNORS AND LINKAGE .................
22
GENERAL INFORMATION ............................................. 22
OPERATION .................................................................... 22
TROUBLESHOOTING .................................................... 22
ENGINE OVERSPEEDING ............................................. 22
ENGINE SURGING ......................................................... 22
SERVICE ......................................................................... 23
GOVERNOR ADJUSTMENT .......................................... 23
GOVERNOR GEAR AND SHAFT SERVICE .................. 23
GOVERNOR GEAR OR SHAFT REPLACEMENT,
UPSET STYLE GOVERNOR SHAFT .......................... 23
GOVERNOR SHAFT REPLACEMENT, RETAINING
RING STYLE ................................................................ 24
SPEED CONTROLS AND LINKAGE .............................. 25
CONVERSION TO REMOTE CONTROL ....................... 27
OVM, OVXL, OHV VERTICAL SPEED CONTROL ........ 28
OHV 11-17 HORIZONTAL SPEED CONTROL............... 28
CHAPTER 5 RECOIL STARTERS .................................
29
GENERAL INFORMATION ............................................. 29
OPERATION .................................................................... 29
COMPONENTS ............................................................... 29
SERVICE ......................................................................... 29
ROPE SERVICE .............................................................. 29
ROPE RETAINER REPLACEMENT ............................... 30
STYLIZED REWIND STARTER (OHH, OVRM, OHM,
OHSK, OVM, OVXL, OHV 11-13), AND STAMPED
STEEL STARTER ......................................................... 30
DISASSEMBLY PROCEDURE ....................................... 30
ASSEMBLY PROCEDURE ............................................. 31
STYLIZED REWIND STARTER WITH PLASTIC
RETAINER .................................................................... 31
DISASSEMBLY PROCEDURE ....................................... 31
ASSEMBLY ...................................................................... 32
KEEPER SPRING STYLE STARTERS .......................... 32
DISASSEMBLY PROCEDURE ....................................... 32
ASSEMBLY PROCEDURE ............................................. 33
STYLIZED STARTER (OHV 13.5 -17) ............................ 34
ASSEMBLY ...................................................................... 34
CHAPTER 6 ELECTRICAL SYSTEMS ..........................
35
GENERAL INFORMATION ............................................. 35
OPERATION .................................................................... 35
STARTING CIRCUIT AND ELECTRIC STARTERS ....... 35
CHARGING CIRCUIT ...................................................... 35
CONVERTING ALTERNATING CURRENT TO
DIRECT CURRENT ...................................................... 36
HALF WAVE RECTIFIER SINGLE DIODE ..................... 36
FULL WAVE RECTIFIER BRIDGE RECTIFIER ............. 36
COMPONENTS ............................................................... 36
BATTERY......................................................................... 36
WIRING ............................................................................ 36
ELECTRICAL TERMS ..................................................... 37
BASIC CHECKS .............................................................. 37
TROUBLESHOOTING ELECTRICAL STARTER
CIRCUIT FLOW CHART .............................................. 38
TROUBLESHOOTING ELECTRICAL CHARGING
CIRCUIT FLOW CHART .............................................. 39
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