Yamabiko ECHO SRM-420ES - Service Information

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SRM-420ES, SRM-420TES
T410S, B410S
T410TS, B410TS
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TABLE OF CONTENTS
Page Page
1 SERVICE INFORMATION
..................................... 2
1-1 Specifi cations ...................................................2
1-2 Technical data ..................................................4
1-3 Torque limits .....................................................5
1-4 Special repairing materials ...............................5
1-5 Service Limits ...................................................6
1-6 Special tools .....................................................7
2 STARTER SYSTEM
..............................................8
2-1 Disassembling starter assembly .......................9
2-2 Replacing starter rope ....................................10
2-3 Installing rewind spring ...................................11
2-4 Assembling starter ..........................................11
2-5 Replacing starter pawl ....................................13
3 IGNITION SYSTEM
............................................. 14
3-1 Troubleshooting guide ....................................14
3-2 Testing spark ..................................................15
3-3 Inspecting spark plug .....................................15
3-4 Inspecting ignition switch ................................16
3-5 Replacing ignition switch ................................17
3-6 Inspecting ignition coil resistance ...................21
3-7 Replacing spark plug cap and coil..................21
3-8 Replacing ignition coil .....................................22
3-9 Setting pole shoe air gaps ..............................22
3-10 Inspecting fl ywheel and key ...........................23
4 FUEL SYSTEM
...................................................24
4-1 Inspecting air fi lter ..........................................25
4-2 Inspecting fuel cap and fuel strainer...............25
4-3 Inspecting fuel tank and tank vent ..................26
4-4 Replacing fuel line, fuel return line, tank vent
line and grommet ............................................28
4-5 Adjusting carburetor .......................................30
4-5-1 General adjusting rules ..................................30
4-5-2 Throttle adjust screw, L mixture needle and
H mixture needle initial settings ......................30
4-5-3 Adjusting carburetor .......................................31
4-6 Testing carburetor ...........................................32
4-7 Inspecting crankcase pulse passage .............33
4-8 Inspecting metering lever height ....................33
4-9 Inspecting inlet needle valve ..........................34
4-10 Inspecting diaphragm and others ...................34
4-11 Replacing welch plug .....................................35
4-12 Replacing purge bulb .....................................35
4-13 Replacing throttle cable and control parts ......36
4-14 Checking and adjusting throttle cable ............36
5 CLUTCH SYSTEM
..............................................37
5-1 Removing clutch shoes and springs ...............38
5-2 Installing clutch shoes ....................................38
5-3 Removing clutch drum ....................................39
5-4 Removing clutch drum bearings .....................39
5-5 Installing bearings and clutch drum ................40
6 ENGINE
............................................................... 41
6-1 Testing cylinder compression .........................42
6-2 Cleaning cooling air passages .......................42
6-3 Inspecting muffl er and exhaust port ...............43
6-4 Testing crankcase and cylinder sealing ..........44
6-5 Removing and inspecting cylinder ..................44
6-6 Inspecting piston and piston ring ....................45
6-7 Inspecting crankcase and crankshaft .............46
6-8 Replacing oil seal ...........................................46
6-9 Replacing ball bearing ....................................47
6-10 Assembling crankshaft and crankcase ...........48
6-11 Installing piston ...............................................48
6-12 Installing piston ring and cylinder ...................49
7 CUTTER DRIVE SYSTEM
..................................50
7-1 Replacing drive shaft ......................................50
7-2 Disassembling gear case ...............................51
7-3 Replacing gears and PTO shaft .....................52
7-4 Assembling gear case ....................................54
8 MAINTENANCE GUIDE
......................................55
8-1 Disassembly Chart .........................................55
8-2 Troubleshooting guide ....................................56
8-3 Service Intervals .............................................58