Alternator whistle
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Joined: May 2019
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Alternator whistle
I'm getting a very slight whistle when I accelerate slowly at lower speeds ....when I let off the gas the whistle stops or if I hit the gas harder the whistle goes away..... it's only at certain RPMs and speeds.. it's not a squeaking it's a whistle.... any ideas ????....and if I need a new alternator what's the best one to get for a 1980 with an L48 engine that's been modified
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Joined: Mar 2017
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From: Virginia
Can you get it to whistle with the car parked? A mechanics stethoscope, or even a piece of vacuum tube held up to your ear, can help you confirm the location of noises. Could it be a vacuum leak you hear?
I put a Powermaster 150A 12SI alternator in my L48 80 when the stock alternator couldn't keep up with the headlights. Now it runs a dual-Spal fan.
I put a Powermaster 150A 12SI alternator in my L48 80 when the stock alternator couldn't keep up with the headlights. Now it runs a dual-Spal fan.
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Joined: Jul 2015
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From: SW Florida.
And alternator will make a high pitched low volume whistling sound when it's charging. You know the way you can hear of 60 cycle hum from fluorescent lights and some other things? Well that whistle is the sound of 3 phase at your engine rpm's. If loud, it could be blown diode or 1 phase of alt winding shorted to ground.
Last edited by derekderek; Feb 23, 2020 at 10:02 AM.
