Bad alternator - not carging at idle

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kapitein

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Joined
Jul 14, 2024
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Location
Netherlands
First Name
Alex
Truck Year
1986
Truck Model
C20 Suburban
Engine Size
454
Howdy folks,

I think I know the answer, but never hurts to ask.

86 454. Std alternator (doesnt look old, but I dont know its history).

Car has quad LED headlight upgrade and electric fan conversion.

At idle with everything switched on (incl. AC) its only reading 12.4v at the battery.

Going down the road it charges nicely at 14.3-14.4v

With the summer season approaching, its going to be using a lot of AC and probably sitting a lot in traffic on the highway, so I want to get this solved.

Sound like a duff alternator? Reading the forums, it seems like throwing on a CS130 is the default answer - sound about right?

Thanks
 

Edelbrock

Full Access Member
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Location
Earth
First Name
Grumba
Truck Year
1977
Truck Model
K5 Blazer
Engine Size
400
What is your idle speed? Wrong size alternator pulley? Bad voltage regulator?
 

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