PGO Bug Rider BR-250, Руководство по обслуживанию

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8
. CARBURETOR
BR & M2 250 ENGINE
8-5 AUTO-ENRICHENER (AUTO-CHOKE) SYSTEM
The automatic enrichener (automatic choke) device consists of the PTC heater A, the
thermo-wax B and the plunger/needle
•
. When the thermo-wax B is cold, the plunger/needle
•
moves upward, Fuel is drawn into the enrichener circuit from the float chamber
‚
.
Enrichener jet
ƒ
meters this fuel, which then flows into fuel pipe
„
and mixes with
the air coming From the upper part of the float chamber … . The mixture, rich in fuel
content, reaches upper part of The fuel pipe and mixes again with the air coming through
a passage extending from main bore
†
. The two succesive mixings of fuel with air are
such that proper fuel/air mixture for starting is produced when the mixture is sprayed
out through outlet port
‡
into the main bore.
NOTE:
An enrichener is operated almost the same way as a choke.
When the engine is cold:
The automatic enrichener passage is always open as the thermo-wax remains atomospheric
temperature.
When the engine is started:
According to the PTC heater temperature, the thermo-wax gradually expands and closes
enrichener passage by the needle of the plunger.