Voltimeter/Regulator

[78Jimmyish]

My voltimeter fluctuates quite a bit when I'm driving. At idle it sits right at 12/13, but when I'm driving it fluctuates from about 10/11 to 15/16 - never hits near the red on either end, but if I'm driving at night with the headlights on they dim and brighten as the meter fluxes. Does that sound like the regulator or something else?

 

['73 K5]

Sounds like either a bad gauge or yea, the voltage regulator is messing up.

'73 K5
Chevy good...Ford bad

 

[dyeager535]

Get a voltemeter (actual seperate one) and hook it up to the battery, and watch it as you rev the motor up, turn on lights, etc. If you get a lot of jumping, its an alternator problem. If its pretty steady (although it will go down under load to maybe 12.5 or so ideally) then it would be in the gauge.

Dorian
My tech/links page: <a target="_blank" href=http://www.dorianyeager.com/index2.html>http://www.dorianyeager.com/index2.html</a>
No anti-theft measures on your truck? No pity when its stolen

 

[78Jimmyish]

Cool, I have a voltimeter. If I hook it up to the battery and it jumps (matches the gauge) should I replace the regulator first, or is it the alternator for sure?

 

[dyeager535]

Well, I'm not totally sure, so I can't with certainty say. i just don't know enough about the alternators to know if that problem would be regulator. My guess is yes, but am I positive? No. I believe you can get rebuild kits for $15-20, and they are easy to do.I believe you replace most everything that wears out (typically) in the alternators with one of the kits.

Dorian
My tech/links page: <a target="_blank" href=http://www.dorianyeager.com/index2.html>http://www.dorianyeager.com/index2.html</a>
No anti-theft measures on your truck? No pity when its stolen

 

[Seventy4Blazer]

ethier way it is easier and more cost efective to start at the regulator.
Grant

1974 Chevy Blazer Cheyanne. but it is on 33's now, with saggy old springs. i am in Yuma Arizona if ya got any parts for me.

 

[78Jimmyish]

Yeah, that makes sense. I'd rather replace the $15 regulator first.