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12. AUTOMATIC DECOMPRESSION SYSTEM
12-1 FUNCTIONS AND CONSTRUCTION
EK series engines employ an automatic decompression system as a standard feature. This enables
easy starting of the engine, with lighter recoil pulling force.
The automatic decompression system releases the compression of the engine by lifting up the tappet for
exhaust valve at cranking speed. The following is the explanation of the function.
When starting engine, the flyweight is pulled by spring and lifts up the decompression pin.
Then, tappet (exhaust) which in turn opens up the exhaust valve slightly to release the compression,
accordingly recoil pulling force become lighter.
When the cranking speed reaches specified r.p.m., flyweight move to outer against spring force
because the centrifugal force applied to the flyweight and the decompression pin coming down.
Then ,Tappet coming down to normal position to follow the cam profile not to release compression.
12-2 INSPECTION
When assembling the release lever, make sure that it works smoothly.
Tappet
Flyweight
Flyweight
Spring
Decompression pin
Summary of Contents for EK13
Page 1: ...EK13 EK1 7 EK20 EK28 EK30 ...
Page 2: ...2 ...
Page 14: ...14 4 17 DIMENSIONS B Type D Type ...
Page 54: ...54 11 OIL SENSOR Not available ...
Page 65: ...65 15 2 ELECTRIC STARTER ...