WARNING
Make sure the spark plug is away
from the spark plug hole in the cylin
der so the spark cannot ignite the mix
ture in that cylinder. If the engine is
flooded, do not perform this test. The
firing of the spark plug can ignite fuel
ejected from the opened spark plug
hole.
WARNING
During the next step, do not hold the
spark plug, plug wire or connector
with your fingers. Serious electrical
shock may result.
3. Turn the main switch on, and crank the engine
over with the starter. A fat blue spark should be evi-
dent across the plug terminals. Repeat this test for
the other cylinder.
4. Repeat Steps 1-3 for the other spark plug.
5. If the spark is good at each spark plug, the igni-
tion system is functioning properly. Check for one
or more of the following possible malfunctions:
a. Obstructed fuel line or fuel filter.
b. Damaged fuel pump system.
c. Low compression or engine damage.
d. Flooded engine.
6. If the spark was weak or if there was no spark at
one or more plugs, note the following:
a. If there is no spark at both plugs, there may be
a problem in the input side of the ignition sys-
tem, ignitor unit, sidestand switch or neutral
switch. Troubleshoot the ignition system as
described this chapter.
b. If there is no spark at only one spark plug ,
the spark plug is probably faulty or there is a
problem with that spark plug’s wire, plug
cap or ignition coil. Retest it with a spark
tester or use a new spark plug. If there is still
no spark at that plug, make sure the spark
plug cap is installed correctly. Check the
spark plug wiring and cap, and test the re-
lated ignition coil as described in Chapter
Nine.
Engine is Difficult to Start
1. Check for fuel flow to the carburetors. If fuel is
reaching the carburetors, go to Step 2. If not, check
for one or more of the following possible malfunc-
tions:
a. Clogged fuel hose and/or fuel filter.
b. Clogged fuel tank breather hose.
c. Damaged fuel pump.
d. Damaged starting circuit cutoff relay.
e. Loose or disconnected starting circuit cutoff
relay connector.
2. Perform the
Spark Test
described in this section.
Note the following:
a. If the spark plugs are wet, go to Step 3.
b. If the spark is weak or if there is no spark, go
to Step 4.
c. If the spark is good, go to Step 5.
3. If the plugs are wet, the engine may be flooded.
Check the following:
a. Flooded carburetors.
b. Dirty air filter.
c. Throttle valve(s) binding or stuck open.
d. Incorrect choke operation.
e. Needle valve in carburetor stuck open.
4. If the spark is weak or if there is no spark, check
the following:
a. Fouled spark plug(s).
b. Damaged spark plug(s).
c. Loose or damaged spark plug wire(s).
d. Loose or damaged spark plug cap(s).
e. Damaged ignitor unit.
f. Damaged ignition coil.
g. Damaged engine stop switch.
h. Damaged ignition switch.
i. Damaged sidestand switch.
j. Dirty or loose terminals.
38
CHAPTER TWO
5
