SERVICE MANUAL NUMBER 24
TROUBLESHOOTING
Testing Thunderbolt V Ignition System
Check to ensure that tachometer GRY lead is not
shorted to ground (-) at the tachometer or within the
harness.
No Spark
Check all terminal connections at distributor, ignition module and ignition coil.
Battery OK?
Distributor clamping screw tight?
No Spark
Check
engine and
instrument
wiring har-
ness, battery
cables, key
switch.
With key in RUN position, check for 12 volts at
positive (+) terminal on ignition coil.
0
Volts
Unplug WHT/RED bullet connector from distributor.
Check for 12 volts on lead coming from module.
0
Volts
12
Volts
Reconnect WHT/RED bullet connectors. Remove
high-tension lead from distributor to coil. Insert a
spark gap tester form coil tower to ground. Discon-
nect WHT/GRN lead from distributor. Place ignition
key in RUN position. Rapidly strike the terminal of
the WHT/GRN lead that comes from module,
against ground (-).
Replace igni-
tion sensor
in distributor.
Spark at
coil.
No spark at coil.
Substitute a new ignition coil. Repeat above
test.
Spark at
coil.
Install new
ignition coil.
No spark at coil.
Replace ignition module.
IMPORTANT: The WHT/GRN lead must be touched against ground (–) 2-3 times per
second to simulate a running engine. Repeat this test several times to ensure that
spark is present.
Index
90-861327--1
OCTOBER 1999
Page 1C-9
Product Specification
Categories | Mercury MerCruiser Manuals |
---|---|
Tags | Mercury MerCruiser 305 CID, Mercury MerCruiser 350 CID |
Model Year | 1998, 1999, 2000, 2001 |
Download File |
|
Document File Type | |
Copyright | Attribution Non-commercial |
Great performance engine.
Class 1