IGNITION
SYSTEM
In order to receive satisfactory performance from the
ignition system, all components must be in good
condition and the spark must be properly
timed.
Hard
starting,
low power and erratic operation can often be
caused by faulty ignition. If poor ignition is
suspected,
the first thing to do is to determine if the
ignition system is actually at fault. A simple
operational test will determine this.
IGNITION
TEST
Remove the high tension leads from the spark plugs
(Figure 12) and hold the end terminal approximately
3/16 inch from a clean metal part of theengine. Crank
the engine to produce a spark. If a sharp, snappy
spark occurs, the trouble apparently is not in the
coil,
condenser, or breaker points although it could be in
the spark plugs. If thereisnosparkoronethatisweak
or yellowish in color, ignition trouble is indicated.
High Tension Leads: Inspect ignition leads forcracks
or breaks in the insulation that may weaken the
current before it reaches a plug. A high tension wire
touching metal at some point may make operation
unsatisfactory.
Spark Plug: Engine misfire or generally poor opera-
tion is often caused by a spark plug in poor condition
or with the wrong gap setting. Remove the spark
plugs and carefully check for the following
con-
ditions:
• Porcelain insulator cracked or coated with oil.
• Electrodes burned or worn away.
• Wrong gap setting (Figure 13).
If the porcelain insulator is cracked or broken or if the
electrodes are badly worn or burned, replace the
spark plug with a new one.
If not, it can probably be restored to good operating
condition by the following steps:
1.
Degrease wet or oily plug and dry thoroughly.
2.
File center electrode to a flat surface.
3. Adjust gap to .025". Use a round wire gauge for
more accurate measurement.
4.
Install plug. Tighten to torque value of 15-20 ft.
pounds.
BREAKER
MECHANISM
HIGH TENSION
LEADS
FIGURE 12. IGNITION SYSTEM
21
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