DIAGNOSTICS
SERVICE MANUAL NUMBER 24
Chart A-7 (5 of 6): Ignition System Check
Step
Action
Yes
No
PROCEED TO
a. Disconnect distributor 4-wire connector.
b. Remove distributor cap.
c. Disconnect pick-up coil connector from the distributor
ignition control module.
d. Connect D\/OM to CKT 121 tach terminal at the 5-way
or 6-way harness connector and ground.
10.
Step 11. Step 20.
e. Ignition ON, engine OFF.
f.
Connect positive (+) end of a known good 1.5 volt test
battery to the “P” terminal on the distributor ignition con-
trol module. Observe the voltage at the tach terminal as
the negative (-) end of the test battery is momentarily
grounded to a known good ground.
Does The Voltage Drop?
Check for spark from the coil wire as the test battery lead
is removed?
11.
Step 16. Step 12.
Is Adequate Spark Present?
Replace ignition coil and recheck for spark using Steps 10.
and 11.
12.
13.
Step 13.
–
–
Is Adequate Spark Present?
Reinstall coil and check coil wire from distributor cap. If OK,
replace ignition module.
Check for faulty connections or open tach lead. If OK,
replace ignition module and recheck for spark using Steps
Verify
Repair
14.
Step 15.
–
10.
and 11.
Is Adequate Spark Present?
Replace ignition coil.
15.
16.
17.
Is the rotating pole piece still magnetized?
Replace faulty pick-up coil.
Step 17. Step 21.
Inspect distributor cap for water, cracks, etc. If OK, replace
faulty distributor rotor.
18.
Check for open or short to ground in CKT 3, open CKT 902,
open or short to ground in CKT 121. If OK, replace faulty
ignition coil.
19.
Verify
–
Check ignition module ground. If OK, replace faulty ignition
module.
Repair
20.
21.
22.
23.
Replace distributor pole piece and shaft assembly.
A mechanical repair will be necessary before continuing
with this test.
Locate and repair intermittent faulty connections.
Index
Page 5G-42
90-861327--1 OCTOBER 1999
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