1) Replace fuel hoses (pipe to fuel pump, pipe to
fuel filter and breather hose) in fuel feed and
return lines with new ones.
2) Remove fuel tank.
3) Replace return hose (tank to return pipe)
with new one.
4) Clamp hoses securely.
5) Install fuel tank referring to p. 4-35.
6) After installation, start engine and check it
for leaks.
27. IDLE SPEED INSPECTION
NOTE:
Before starting engine, place transmission gear
shift lever in “Neutral”, and set parking brake
and block drive wheels.
1) Warm up engine to normal operating tempe-
rature.
2) Check to ensure that idle speed is within
750
-
850
r/min
(rpm).
3) If idle speed is not within specified range,
adjust idle speed. Refer to MAINTENANCE
SERVICE (p. 4-26) for procedures to check
and adjust idle speed.
28. IDLE MIXTURE INSPECTION
1) Warm up engine to normal operating tem-
perature.
2) Remove seal rubber of duty check coupler
and connect positive terminal of duty meter
to “Blue/Red” wire and negative terminal to
“Black/Green” wire.
1
1. Duty check coupler
2. Air intake case
3) Set tachometer.
4) Run engine at 1,500
-
2,000
r/min
for 30
seconds and bring it to idle speed.
5) Check duty at specified idle speed. If it is out
of specification, adjust it to specification
according to following adjustment procedure.
Specified Duty
10-50
at 750
-
850 r/min.
I
After inspection, install seal rubber to duty
check coupler.
Idle mixture adjustment procedure is as follows:
1) Remove carburetor from intake manifold
following normal service procedure to gain
access to mixture adjusting screw pin covering
mixture adjusting screw.
2) Drive out mixture adjusting screw pin using
about 4.5 mm (0.18 in) thick iron rod as
shown below.
1-15