Tecumseh HS40 User Manual

i
C Tecumseh Products Company
1998
CONTENTS
CHAPTER 1 GENERAL INFORMATION........................................................................................................ 1
ENGINE IDENTIFICATION.............................................................................................................................. 1
INTERPRETATION OF MODEL NUMBER...................................................................................................... 1
SHORT BLOCKS............................................................................................................................................. 2
FUEL................................................................................................................................................................ 2
ENGINE OIL .................................................................................................................................................... 3
TUNE-UP PROCEDURE ................................................................................................................................. 3
STORAGE........................................................................................................................................................ 4
CHAPTER 2 AIR CLEANERS ....................................................................................................................... 5
GENERAL INFORMATION .............................................................................................................................. 5
OPERATION .................................................................................................................................................... 5
COMPONENTS ............................................................................................................................................... 5
TROUBLESHOOTING OR TESTING.............................................................................................................. 5
SERVICE ......................................................................................................................................................... 6
DISASSEMBLY PROCEDURE........................................................................................................................ 6
POLYURETHANE-TYPE FILTER ELEMENT .................................................................................................. 6
PAPER-TYPE FILTER ELEMENT ................................................................................................................... 6
CHAPTER 3 CARBURETORS AND FUEL SYSTEMS .................................................................................. 7
GENERAL INFORMATION .............................................................................................................................. 7
OPERATION .................................................................................................................................................... 8
FUEL PRIMERS............................................................................................................................................... 8
IMPULSE FUEL PUMPS ................................................................................................................................. 9
FLOAT STYLE CARBURETORS..................................................................................................................... 9
DIAPHRAGM (PRESSURE DIFFERENTIAL) CARBURETORS..................................................................... 9
COMPONENTS ............................................................................................................................................. 10
CARBURETOR IDENTIFICATION ................................................................................................................ 11
DUAL SYSTEM CARBURETORS ................................................................................................................. 11
SERIES 1 CARBURETORS .......................................................................................................................... 11
SERIES 3 & 4 CARBURETORS.................................................................................................................... 11
DIAPHRAGM CARBURETORS..................................................................................................................... 11
SERIES 6 CARBURETORS 4-CYCLE.......................................................................................................... 12
SERIES 8....................................................................................................................................................... 12
SERIES 9....................................................................................................................................................... 12
SERIES 10 (EMISSION)................................................................................................................................ 12
NON-TECUMSEH CARBURETORS -- DELLORTO CARBURETOR.......................................................... 12
ENGINE TROUBLESHOOTING CHART....................................................................................................... 13
CARBURETION TROUBLESHOOTING CHART .......................................................................................... 14
TESTING ....................................................................................................................................................... 15
SERVICE ....................................................................................................................................................... 15
CARBURETOR PRE-SETS AND ADJUSTMENTS ...................................................................................... 15
FINAL ADJUSTMENTS (NON-EMISSION ENGINES).................................................................................. 16
NON-ADJUSTABLE CARBURETOR............................................................................................................. 16
DISASSEMBLY PROCEDURE...................................................................................................................... 17
FLOAT STYLE CARBURETORS................................................................................................................... 17
DIAPHRAGM CARBURETORS..................................................................................................................... 19
FLOAT ADJUSTING PROCEDURE .............................................................................................................. 19
INSPECTION ................................................................................................................................................. 20
ASSEMBLY .................................................................................................................................................... 21
STANDARD SERVICE CARBURETORS ...................................................................................................... 24
CHAPTER 4 GOVERNORS AND LINKAGE ................................................................................................ 26
GENERAL INFORMATION ............................................................................................................................ 26
OPERATION .................................................................................................................................................. 26
INTERNAL COMPONENTS (VARIOUS STYLES) ........................................................................................ 26
TROUBLESHOOTING................................................................................................................................... 26
ENGINE OVERSPEEDING ........................................................................................................................... 27
ENGINE SURGING ....................................................................................................................................... 27
SERVICE ....................................................................................................................................................... 27
GOVERNOR ADJUSTMENT......................................................................................................................... 27
GOVERNOR ADJUSTMENT PROCEDURE FOR SHORT BLOCK INSTALLATIONS................................. 27

Tecumseh HS40 Specifications

General

Fuel Type	Gasoline
Cooling System	Air-cooled
Ignition System	Magneto
Starting System	Recoil
Engine Type	4-stroke, single cylinder, air-cooled
Power	4 HP
Oil Capacity	20 oz (0.6 L)