Disassembling The Carburetor; Checking The Carburetor - Yamaha E40G Service Manual

Disassembling the carburetor

NOTE:
9 Before disassembling the carburetor, make
sure to note the number of times the pilot
screw is turned out from the seated position
to its set position.
9 Disassembled jets and other components
should be sorted out and kept in order, so
that they can be re-assembled in their orig-
inal positions.

Checking the carburetor

1. Check the air and fuel passages and jets,
for dirt and foreign matter. Clean the car-
buretor body with a petroleum based sol-
vent if necessary.
2. Blow compressed air into all passages
and jets.
cC
9 Direct the compressed air downward,
otherwise cleaning solvent may be
blown into your eyes or small parts of
the carburetor may be blown off.
9 Do not use steel wire for cleaning the
jets, otherwise the jet diameters may be
enlarged, which may seriously affect
performance.
3. Check the main jet, pilot jet, and main
nozzle for dirt or residue. Clean if neces-
sary.
6F65G11
4. Check the pilot screw and needle valve
for bends or wear. Replace if necessary.
5. Check the float for deterioration. Replace
if necessary.
6. Measure the float height a. Replace the
float and needle valve as a set, if out of
specification.
NOTE:
6D440025
9 The float should be resting on the needle
valve 1, but not compressing it.
9 Measure the height a from the gasket to
the float as shown.
2
a
Digital caliper 2: 90890-06704
Float height a:
12.5—13.0 mm (0.47—0.51 in)
Carburetor
1
2
6B440040
3
4
5
1
6F640060
6
7
8
9
4-8