Too Much Voltage

[Jackpot50]

Got in my car the other day to move it, had been setting for a week with out battery hooked up.
Started showing 15V at Idle and 18V at 3000 RPM.
Changed VR no change checked diodes all show resistance one way.
Optima battery it shows 12.7 with engine off and 15V when running at Idle.
Was working fine before last week. Alternator is maybe 8 months old.:icon_scratch:
Any Ideas all out

 

[Hemi Rebel]

Must be getting full voltage to alternator field circuit. Check voltage coming into alternator field circuit at back of alternator with the engine running.
Why type of charging system do you have?

 

[ram250098]

I had this problem in one of my cars..alt looked new...changed voltage reg..etc etc.
Took the alt in and had it checked, everything ok. I ended up swapping in another alt and it was fine.
I tried the one I took out in another car and it was showing over 18v....so it was the alt after all even after the rebuilders said it was fine.
AL

 

[super-bee_ski]

Id say so too...
Reasom being, no transformers in a car circuit.
(Except for the coil)
The Alternator is the only subsystem producing electricity...

 

[Jackpot50]

90 amp high out put alternator square back

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Any way to check alternator

 

[super-bee_ski]

Personally?
I would PULL said alternator and take it to the local NAPA store and have them check it out!

I know how to check them, but to keep it simple here...you should pull it and the NAPA store will check it out for you.

Here ya go:
NAPA: 1504 W Broadway St, Princeton, IN 47670
(812) 385-2500

 

[HT413]

I went through this a year or so ago. For me, the equipment was fine. I had a lot of resistance in the harness that was showing a lower voltage to the alternator, forcing it to overcharge.

Before throwing parts at it, check out my thread. Let me find the link...

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http://www.forbbodiesonly.com/moparforum/showthread.php?56124-How-I-fixed-my-overcharging-issues

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I was seeing 17V and fixed it with salt and vinegar.

 

[Jackpot50]

Found problem when checked blue wire to VR with key on, no voltage had voltage at field on alternator.
Pulled wires out of wire wrap it was nor connected guess I did this when wired car? trying to figure how it worked before and not had high voltage. hooked up right 14.5 at 3000. Thanks for all your help!

 

[super-bee_ski]

I went through this a year or so ago. For me, the equipment was fine. I had a lot of resistance in the harness that was showing a lower voltage to the alternator, forcing it to overcharge.

Before throwing parts at it, check out my thread. Let me find the link...

- - - Updated - - -

http://www.forbbodiesonly.com/moparforum/showthread.php?56124-How-I-fixed-my-overcharging-issues

- - - Updated - - -

I was seeing 17V and fixed it with salt and vinegar.

KOOL HT413!
Thanks for that POST!


HeyJackpot50:
Glad you found the problem.
NAPA auto store provide a great AND free service..Alternator diagnostics checkout

 

[Donny]

Now THIS is too much voltage! https://www.youtube.com/watch?v=tJ_bQiTU04c

 

[Meep-Meep]

Damn! Did you see towards the end that 4th guy get up and run away?

 

[Hemi Rebel]

Holy crap!