TROUBLESHOOTING
SERVICE MANUAL NUMBER 23
Page 1C-12
90-861326--1 MARCH 1999
Noisy Alternator
Cause
Special Information
Loose mounting bolts
Drive belt
Worn, frayed, loose
Loose drive pulley
Worn or dirty bearings
Faulty diode trio or stator
Instrumentation Malfunction
Cause
Special Information
Faulty wiring, loose or corroded terminals
Faulty key switch
Test, as outlined in SECTION 4D
Faulty gauge
Test, as outlined in SECTION 4D
Faulty sender
Test, as outlined in SECTION 4D
Radio Noise
Cause
Special Information
A “popping” noise that will increase with
engine rpm. Noise will stop as soon as en-
gine is turned off.
Ignition System - wrong spark plugs;
cracked distributor cap; cracked coil tower;
leaking spark plug wires; moisture on
ignition components
“High pitched whine” in the radio
Alternator - poor brush contact on the slip
rings
A “hissing or crackling” noise when instru-
ments are jarred with ignition on
Instrumentation - loose connections, or
antennae wire routed too close to instru-
ments
Varying unexplained noises
Accessories - bilge pump, bilge blower;
fish finder, depth locator; cabin heater
motor, etc. Disconnect one at a time until
noise disappears.
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Index
Index