Honda CB350 Repair Manual page 108

FUEL SYSTEM 103
Check the needle for wear
More often, however, these components
will need to be replaced because of nor—
mal wear. As the throttle slide moves up
and down while the machine is in opera—
tion, the needle is rubbing against the jet.
Eventually, these components will wear
enough to cause a noticeable rich run—
ning condition in the mid—throttle range.
If this occurs, both the needle and the jet
should be replaced. If the components
are more than four years old, new ones
should be fitted before attempting to tune
the carburetor, or taking remedial action
to correct a rich condition (such as lower—
ing the needle).
6. Carefully inspect the floats. If brass
floats are fitted, shake the float close to
your ear; listen for any gasoline trapped
inside. If the float assembly leaks, orif
any puncture is noted, replace it; do not
attempt repairs.
7. Check that both floats are at exactly
the same level, with one not twisted
higher or lower than the other. If this is
the case, the floats have been mishan—
dled, and must be replaced.
Inspect the tip of the float needle and
the needle seat for dirt or corrosion.
Check the needle tip for wear. If worn,
the needle should be replaced.
If there is any corrosion or deposits evi—
dent on the needle or needle seat, the de—
posits must be removed, or the parts re—
placed.
NOTE: Do not attempt to clean the
needle or needle seat by lapping one
against the other.
To check the efficiency of the float
needle valve, proceed as follows:
a. With the carburetor assembled
except for the float bowl, connect it to
its fuel line;
b. Place a number of dry rags be—
neath the carburetor, and hold it
upright (in its normal operating posi—
tion) with one hand;
c. With the other hand, gently raise
the float assembly until the float needle
is seated. Have an assistant turn the
fuel petcock on;
d. If the needle and seat are in good
condition and forming a good seal, no
gasoline will flowout ofthe carburetor;
e. If a leak is noted, replace the
needle and seat.
CAUTION: While performing this
test, be sure that adequate precautions
are taken in the event of spillage.
Pilot air screw taper must be smooth
The float level should be checked prior
to assembly. Refer to Chapter 3.
8. Check that the tapered portion of
the pilot air screw is smooth and clean.
Replace it if it is crushed or blunted.
Assembly
Assembly is basically the reverse ofthe
disassembly procedures, but note the fol—
lowing points:
1. Float bowl gaskets and jet O—rings
should always be replaced with new
ones. Other O—rings and fiber gaskets
should be carefully inspected and re—
placed if less than perfect in condition.
Check O—rings for tears and cracks; fiber
gaskets for a crushed condition.
2. Exercise care when installing jets,
they are made ofsoft brass and are easily
damaged if overtightened. Install the
needle jet, main jet holder, main jet, pilot
jet, and float needle seat.
3. Install the float needle into its seat.