Yamaha SRX440 1980 Service Manual page 43

carburetor with a hard tool. Dust
should be blown off with com-
pressed air.
2) When reinstalling the throttle cable,
make su re the th rottle va Ive can be
fully opened and closed, and make
an adjustment.
1980 SRX440
Trouble Check point
Remedy
Adjustment
Hard starting Insufficient fuel
Add gasoline
Excessive use of starter Clean spark plug
Return starter lever to its home
(Excessively opened choke)
position.
Fuel passage is clogged or Clean
Parts other than carburetor
frozen
Clogged fuel tank air vent. clogged
frozen
fuel filter. or clogged fuel passage
Carburetor
Clogged or frozen air vent clogged
valve
If water collects in float chamber.
clean
(Also check for ice.)
Overflow
Correct See "Overflow
.
adjustment
throttle opening. If incorrect. back it
(Relative troubles)
Pilot screw adjustment Adjust idling speed
out specification. Start the engine
•
Poor performance at low
and turn pilot screw in and out
speeds
1/4 turn each time. When the engine
Poor acceleration
runs faster. back out throttle stop
..
Slow response to throttle
screw so the engine idles at
·
Engine tends to stall
specified speed.
·
Throttle stop screw
Adjust Tightened to much-Engine speed
is higher.
Backed out too much-Engine does
no idle.
Damaged pilot screw
Replace pilot screw
Clogged bypass hole Clean
Clogged or loose slow jet
Clean and retighten Remove slow jet. and blow it out
with compressed air.
Air leaking into carburetor joint Retighten band screw
Defective starter valve seat
Clean or replace
Overflow
Correct See "Overflow. "
Poor performance at
Clogged or loose slow jet
Clean and retighten Remove slow jet, and blow it out
-
mid-range speeds
with compressed air.
(Relative troubles)
Momentary slow response
to throttle
Poor acceleration
Lean mixtures Overhaul carburetor
See "Overflow.
"
Poor performance at normal
Clogged air vent Clean
Remove the air vent pipe.
speeds
and clean.
(Relative troubles)
Clogged or loose main jet
Clean and retighten
Remove main jet and blow it out
Excess fuel consumption
with compressed air.
Poor acceleration
Overflow
Check float and float valve See "Overflow "
and clean
Poor performance at high
Starter valve is left open Fully close valve
Return starter lever to its home
speeds
position
(Relative trouble)
Clogged air vent
Remove and clean
Power loss
Poor acceleration
Clogged or loose main jet"
Clean and retighten Remove main jet. and clean with
compressed air. then install.
.-
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