Service manual

10-6
✰ Carbon deposits on the spark plug
establishes a ‘shunt’ between center
and earth electrodes, that prevents
good sparking and causes misfiring.
Clean the deposits off periodically,
with a spark plug cleaning tool /
machine.
✰ Check spark plug for pitted out the
earth and center electrodes. If the
earth electrode has worn off to a
knife edge and center electrode has
reduced in height, replace it with
new.
Specific Gravity
Fully charged Requires Recharging
1 .24 1 .15
P Check voltage with voltmeter
SPARK PLUG MAINTENANCE
✰ Neglecting the spark plug
maintenance eventually leads to
difficult starting and poor
performance. If the spark is used
for a long period, the electrode
gradually burns away and carbon
builds up along the inside part. Once
in 3000 kms or earlier, the plug
should be removed for inspection,
cleaning and resetting the gap.
Voltage
Fully charged Fully Discharged
13 .2 10.8
INSPECTION
✰ Clean the electrodes and set gap to
0.7 mm to 0.8 mm
✰ Clean the plug in a ‘Spark plug
cleaner cum Tester’
✰ Test the plug for proper sparking
in the tester
Light blue, solid,
continuous spark Spark Plug OK
seen in the tester
Yellow or red spark;
intermittent or no
spark; or side spark Spark Plug
as seen in the tester Not OK
mirror
Electricals