Checking The Magneto Charge Coil And Pick Up Coil; Ignition Timing; Spark Gap Test; Ignition Coil Resistance Test - Yamaha YT175J 1982 Service Manual

Checking the magneto charge coil and
pick up coil
The resistance of the magneto charge coil
and pick up coil are as specified below. To
locate the cause of trouble (broken coil,
short-circuit etc.), measure the resistance
across each lead as shown in chart.
Pickup coil 10Q ± 10% at 20°C (68°F)
Color
(W/R -
B)
Charge coil 300Q ± 10% at 20°C (68°F)
Color
(Br- B)
1. Setthe tester" x
1
Q" position
1. Set the tester
fIX
1 OQ"
position
Ignition timing
See page 2-7 for Ignition timing.
Spark gap test
The entire ignition system can be checked for
misfire and weak spark using the Electro
Tester. If the ignition system will fire across a
sufficient gap, the engine ignition system can
be considered good. If not, proceed with in-
dividual component tests until the problem is
found.
6-2
1. Warm up engine thoroughly so that all
electrical components are at operating
temperature.
2. Stop engine and connect tester as
shown.
8EB
rn
- H - - - _
-(!}
CD
1. Electro-tester
2. Plug wire from coil
3. Spark plug
3.
Start engine and increase spark gap until
misfire occurs. (Test at various rpm's
between idle and red line.)
Minimum spark gap:
9
mm
(0.35
in) at
5,000
r/min
Ignition coil resistance test
Use a Pocket Tester or equivalent ohmmeter
to determine resistance and continuity of
primary and secondary coil windings.
®.
I
I
I
ED
!
CD
,,/
~
+. /
I
- __________ __ I
1. Primary coil resistance check.
2. Secondary coil resistance check.
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