Noisy alternator


Information and questions on GL1500 Goldwings (1988-2000)
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Fuzzyswing
Posts: 36
Joined: Sun Oct 04, 2015 7:10 am
Location: Fulton NY
Motorcycle: 1988 gl1500 1979 kz1000 LTD

Noisy alternator

Post by Fuzzyswing »



I have a 1988 gl1500 after market alternator
It just started making a loud wining noise from the alternator. Replaced both bearings.
Still same problem. When alternator was off I started it and no noise! Any ideas?


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DenverWinger
Posts: 2283
Joined: Thu Jun 23, 2011 2:20 pm
Location: Denver, CO
Motorcycle: (s)
'80 GL1100 STD Vetter (2005-)
'93 GL1500 Aspencade (2017-)
'83 Trav-Lite Camper (2010-)
Past rides
'72 CL350 (1980-1988) sold
'78 Suzuki GS550 (1985-2005) sold
'77 GL1000 (2002-2006) sold

Re: Noisy alternator

Post by DenverWinger »

A shorted diode will suddenly cause an alternator to whine loudly, and eventually will burn out the stator.
There are 10 types of people in the world, those that understand binary numbers, and those that don't. :lol:

♫ 99 Little Bugs in the Code, ♪
♪ 99 Bugs in the Code. ♫ :(
♫ Take one down, Patch it around, ♪
♫ 127 Little Bugs in the Code. ♫ ♪ :shock:
~Mark
Fuzzyswing
Posts: 36
Joined: Sun Oct 04, 2015 7:10 am
Location: Fulton NY
Motorcycle: 1988 gl1500 1979 kz1000 LTD

Re: Noisy alternator

Post by Fuzzyswing »

How do you check the diodes?
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DenverWinger
Posts: 2283
Joined: Thu Jun 23, 2011 2:20 pm
Location: Denver, CO
Motorcycle: (s)
'80 GL1100 STD Vetter (2005-)
'93 GL1500 Aspencade (2017-)
'83 Trav-Lite Camper (2010-)
Past rides
'72 CL350 (1980-1988) sold
'78 Suzuki GS550 (1985-2005) sold
'77 GL1000 (2002-2006) sold

Re: Noisy alternator

Post by DenverWinger »

They're inside the alternator. Six of them.

Check them with an ohm meter, should show continuity in one direction only, if you reverse the ohmmeter leads they should read open circuit.

If you find one of them which shows continuity in both directions it is shorted.

Or you can take the alternator to your friendly starter/alternator rebuilder, they can check it, and even replace a shorted diode.


There are 10 types of people in the world, those that understand binary numbers, and those that don't. :lol:

♫ 99 Little Bugs in the Code, ♪
♪ 99 Bugs in the Code. ♫ :(
♫ Take one down, Patch it around, ♪
♫ 127 Little Bugs in the Code. ♫ ♪ :shock:
~Mark
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