Should the alternator "hum" with key on and engine off?
#1
Should the alternator "hum" with key on and engine off?
Like the topic says. I noticed in the garage when its quiet that if i turn the key on and the engine is off i can hear the alternator "humming". I verified that the sound is from the alt. It seems to be charging alright, i was just concerned about the "humming". Any thoughts?
#3
Re: Should the alternator "hum" with key on and engine off?
Doesnt smell burnt or hot, though i havent left it with just the key on for any length of time (may not want to do that if there is a problem!). Is there any thing in the ECM that could be causing this?
#5
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Car: 1988 GTA
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Re: Should the alternator "hum" with key on and engine off?
I also had this problem, but I've never heard it before on any of the many GM cars I've owned.
I talked to a guy that's an engineer for an alternator manufatcurer, and he says it's a piece of metal that isn't secured exactly right inside the alt. He says it has no bearing on how the alternator functions.
Just for fun, I opened the alt just to take a look. I couln't find anything obvious, so I put it back together and it still humms and charges.
I talked to a guy that's an engineer for an alternator manufatcurer, and he says it's a piece of metal that isn't secured exactly right inside the alt. He says it has no bearing on how the alternator functions.
Just for fun, I opened the alt just to take a look. I couln't find anything obvious, so I put it back together and it still humms and charges.
#7
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Car: 90 Formula WS6, 86 Sport Coupe
Engine: 305 TBI, 2.8 MPFI
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Re: Should the alternator "hum" with key on and engine off?
Forget about it, the alt on my camaro has been doing that for about a year and works perfect. Yours isn't a reman by chance is it? That's what mine is.
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