Author Topic: Electrical gremlin, help?  (Read 1674 times)

Offline Relic

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Electrical gremlin, help?
« on: January 17, 2011 - 03:17:41 PM »
Hey guys,

Ive got a 1970 challenger project that needs to be become my driver before school starts in a 2 weeks. Now when I originally got it running, all the lights lit up, got brighter, flashed, then went out. The dome light actually shattered but I havent checked the other bulbs yet. Any ideas what would cause this?
I was thinking bad voltage regulator or maybe something with the fuses...possibily a bad alternator?? Anything electrical isnt my strong point as you can probably tell from my suggestions lol.
Right now Ive got the alternator disconnected so it wont charge the battery, but that needs to get hooked back up. Any help/suggestions would be great!

Finn from dodgecharger.com




Offline GoodysGotaCuda

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Re: Electrical gremlin, help?
« Reply #1 on: January 17, 2011 - 03:27:31 PM »
Definitely overcharging. The alternator could be the culprit, I'd start with a new voltage regulator and see where that ends up, cheap and fail often. Do not run the vehicle very long overcharging, put a voltmeter on either the back of the alternator (large stud), or battery + to and ground the other lead. Anything over 14v is too high and the problem persists. Be sure to check it above the idle rpm.
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Offline 72rtchallenger

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Re: Electrical gremlin, help?
« Reply #2 on: January 17, 2011 - 06:46:22 PM »
Definitely overcharging. The alternator could be the culprit, I'd start with a new voltage regulator and see where that ends up, cheap and fail often. Do not run the vehicle very long overcharging, put a voltmeter on either the back of the alternator (large stud), or battery + to and ground the other lead. Anything over 14v is too high and the problem persists. Be sure to check it above the idle rpm.
:iagree:  change the regulator and check voltage
72rtchallenger
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Offline Relic

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Re: Electrical gremlin, help?
« Reply #3 on: January 17, 2011 - 09:27:48 PM »
Thanks guys, just picked up a new voltage regulator so Ill pop that in and keep you updated.
Finn from dodgecharger.com

Offline ShelbyDogg

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Re: Electrical gremlin, help?
« Reply #4 on: January 20, 2011 - 06:55:35 PM »
Check your wiring also. If somehow your battery is disconnected from the charging system, the alternator doesn't see a load and will burn out EVERY bulb and electronic device in the car. It happened to me when I put in a battery to replace a dead battery. I started my car, was putting the good battery back in the donor car while my car was running with it's lights on. Car stayed running but all of the lights burn out. Had to drive home with brights on but everything else was off.

I a 70 Challenger, that is a lot of bulbs to have to change all at once. That's around 20 that I can think of right now.
Rob

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Offline ntstlgl1970

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Re: Electrical gremlin, help?
« Reply #5 on: January 20, 2011 - 08:57:26 PM »
Check your wiring also. If somehow your battery is disconnected from the charging system, the alternator doesn't see a load and will burn out EVERY bulb and electronic device in the car. It happened to me when I put in a battery to replace a dead battery. I started my car, was putting the good battery back in the donor car while my car was running with it's lights on. Car stayed running but all of the lights burn out. Had to drive home with brights on but everything else was off.

I a 70 Challenger, that is a lot of bulbs to have to change all at once. That's around 20 that I can think of right now.

:iagree:
I've never seen a mopar voltage regulator fail in the overcharging direction, doesn't mean it can't happen though. No battery load on the alt is 18+ volts easy off idle.
70 Cuda, 7.0L Gen-III Hemi, Viper T56 w/9310 gearset, 3.91's, Megasquirt MS3x v3.57, Innovate wideband, Firm Feel upper arms, torsion bars, springs and strut rods, QA1 DA shocks. I did everything on this car except the fancy paint stuff and I drive it...and I can't seem to stop messing with it....

Offline Relic

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Re: Electrical gremlin, help?
« Reply #6 on: January 22, 2011 - 07:37:51 PM »
Thanks guys, it was a combo of things you all suggested.  :cheers:
I replaced the Voltage regulator, no result. I then pulled the alternator and you could hear the bearings were completely shot so I just went ahead and picked up another one. Put the new one in and still got nothing so I started tracing wires and sure enough, the battery wasn't getting to the alternator. Some quick re-wiring and Ive got one brake light, reverse lights, alternator gauge, blinker/hazard indicators, and wipers working!  :woo: Im assuming the rest is bulbs and/or fuses so Ill check those out tomorrow. Speaking of which, anyone happen to remember the bulb numbers?
Finn from dodgecharger.com

Offline Chryco Psycho

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Re: Electrical gremlin, help?
« Reply #7 on: January 22, 2011 - 09:35:01 PM »
brake & turn are 1157 , revrse is 1156 ,

Challenger - You`ll wish You Hadn`t