Yamaha EK40G, Service Manual

Page: 50 / 200

FUEL
4-9 6H95G11
Fuel system
5. Check the float for deterioration. Replace
if necessary.
6. Measure the float height
a
for the
kerosene and
b
for the gasoline.
Replace the float and needle valve as a
set, if out of specification.
NOTE:
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 for the kerosene side.
9
Measure the height
b
from the gasket to
the float as shown for the gasoline side.
6F640060
a
1
2
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.
c C
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.
4. Check the pilot screw and needle valve
for bends or wear. Replace if necessary.
6D440025
6B440040
Float height
a
: (kerosene)
12.5—13.0 mm (0.47—0.51 in)
Float height
a
: (gasoline)
4.0—5.0 mm (0.16—0.20 in)
Digital caliper
2
: 90890-06704
b
1
6H940065
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