| |
TM 10-3930-653-14&P
4-7-2-3.
Spark plugs
(1)
When engine does not start
If there is no trouble in fuel system.
ignition system should be checked.
This
can
be
easily
done
by
detaching a high tension cable
from spark plug. Turning engine
over with the starter and observing
condition of spark that occurs
between high tension cable and
spark plug terminal. After checking
this .repair as necessary
Spark length
Location
Probable cause
Corrective action
No sparks at all
Distributor
Burnt insulation of condenser.
Replace.
Breakage of lead-wire on low tension side
Repair.
Burnt insulation of cap and rotor head.
Replace.
Points do not open or close
Repair.
Ignition coil
Wire breakage or short circuit of coil
Replace with a new one.
High tension cable
Wire coming off
Repair.
Damaged insulation.
Replace.
1 to 2 mm (0.0394
Distributor
Point gap too wide.
Correct.
to 0.0787 in) or
Oil sticking on points.
Clean.
irregular.
Points burnt too much.
Replace.
Less than 6 mm
Spark plugs
Electrode gap too wide.
Correct or replace.
(0.2362 in)
Too much carbon.
Clean or replace.
Broken neck of insulator.
Replace.
Expiration of plug life.
Replace.
(2)
When engine runs but does
not run smoothly.
In this case, there are many
causes resulting from the ignition
system
and
other
engine
conditions not related to ignition.
Therefore, complete inspection of
ignition system should be carried
out.
Condition
Location
Probable cause
Corrective action
Engine misses.
Distributor
Dirty point.
Clean.
Improper point gap.
Correct.
Leak of electricity between cap and rotor head.
Repair or replace.
Fatigued spring of arm.
Replace assembly.
Worn out or shaky breaker plate.
Replace assembly.
Worn out or shaky distributor shaft.
Replace assembly.
Ignition coil
Layer short circuit or use of inferior quality.
Replace with good one.
High tension code
Deterioration of insulation and leak of
Replace.
Electricity.
Spark plugs
Dirty.
Clean.
Leak of electricity at upper porcelain insu-
Repair or replace.
lator.
4-91
|