Alternator going?

[1979Jimmy]

Latley when i have been starting up my truck the battery gauge shows around 10 volts but after a few miles its back up to a little over 13? Is this normal? I was going to put a better alternator in soon anyway but just curious.

79 Jimmy, 5" lift 35 M/T with a 383 puttin out 400hp and 450lb/ft. Locked front and back.

 

[taterblazer]

That's definetly a bad sign of what I'm not 100% sure. You might check the connection to the alternator. Mine is an 88 and it was shot. Bought a new plastic connector and am much more confident with it. My alternator bearings went out and it was making vibrating noises. Had a friends go out and his voltage gauge just started dropping. Does the volt gauge show alternator ouput or total system voltage? Like maybe the battery is low? Maybe try disconnecting the battery next time you park for the night and see if next time you run it it's still low? Maybe there is a ground in your system? Could be your battery is bad to. At a NAPA or ShUCKS they could probably load test it to check it.

 

[TorkDSR]

sounds more like the battery isnt taking the charge than the alternator isnt giving it. the only other thing could be a bad starter. when they start to go bad, a lot of time there are internal shorts which put a hell of an extra strain on the battery.

Tork DSR
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