Yamaha EF4500iSE Theory & Diagnostics Manual page 22

Yamaha Generator Theory & Diagnostics Guide
EF3000iSE new model guide
Auto-decompression System
All Yamaha generators are equipped with an auto-
EF3000iSE new model guide
decompression system to facilitate engine starting
operation.
While the engine is stationary or running at very low
speed, a pin provided in the camshaft is projected
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above the basic circle of exhaust cam lobe.
The pin, consequently, pushes the valve lifter caus-
ing the exhaust valve to stay open, thus compres-
sion pressure is released.
When the engine speed becomes faster, the decom-
pression weight, which holds the pin in the position,
is thrown out and the pin moves back, thus the
engine can be started as the exhaust valve func-
tions normally.
3/14/03 4:20 PM Page 23
Muffler Cleaning
1. Turn the engine switch to the "STOP" position to
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stop the engine.
2. Loosen the bolt ① and remove the muffler cap
and muffler screen.
3. Remove the carbon deposits on the muffler cap
②, the muffler screen ③ and the spark arrester
④ using a wire brush.
4. Install the muffler screen ③, the muffler cap ②
and the spark arrester ④.
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