charging system not working

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Mar 18, 2007 | 08:15 AM

cobra413

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charging system not working

I have a 1977 f-250 with a 390 and manual tranny. My charging system just stopped working a while ago and I think it is wiring, but not sure. From what I have read in the wiring schematics the only components involved are the alternator, voltage regulator, starter solenoid, and battery. I had the alternator tested and passed, new regulator, and had to get new battery because I drained the old one down too fare to be recharged. I am just wondering if there is any more components than what I listed or am I down to a bad wire? Thanks for your help

Mar 18, 2007 | 02:46 PM

MintFord

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From: Gray, TN

I had trouble with the charging system on my '77 F250. Turned out that the connectors inside the plug to the voltage regulator were too corroded to make good contact. I popped each female spade connector out of the plug and cleaned them up with penetrating oil and a tiny screwdriver. If that doesn't help, there are a few fusible links in that bundle of wires between the alternator and starter solenoid. If you connect the "A" and the "F" terminals of the regulator plug, it should put out maximum charging and prove the alternator is good, but only try it for a second, because you'll be up around 16+ volts. Good luck.

Mar 19, 2007 | 12:10 AM

Alvin in AZ

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From: Gadsden Purchase

Doggonit when it comes to electrical trouble and you ain't got a meter to find the trouble, you can spend more time effort and money than a meter would cost.

The dumb ol' meter will tell you exactly where the trouble is and isn't. :)
Don't know how to "run" one of those meter things? :)

Well you can learn it right here or quicker than that, this might be a good time to call in a favor (or owe a favor) by getting a friend that's got a meter and knows how to use it... find the trouble for you. Quick and easy as that! :)

Believe it or not, it could still be the alternator.

How old's your battery?
Age is a clue but don't mean nuthin without a meter. ;)

Alvin in AZ (retired RR signalape)

Mar 19, 2007 | 03:40 AM

cobra413

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O.k. The battery is brand new. I did take a meter to the wires, but I think it is a wire problem cause all the components check good unless if I bought a bad regulator from the store! No that could never happen from schucks, you think? Ha, Ha. I am just glad it is not my daily driver. thanks for your help so fare I'll let you know what I find out, but it might take a week or two.

Mar 19, 2007 | 03:09 PM

Mil1ion

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Aside from the regular reasons you can get more in-depth info on the charging system in the FTE special electrical forum.

The only part the starter solenoid plays in the charging system is the Lug Power Terminal.

Last edited by Mil1ion; Mar 19, 2007 at 03:11 PM.

Mar 19, 2007 | 10:36 PM

cobra413

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That is a great schematic/drawing. I think I willl take a look ar the connector for the regulator and see if they are corroded. Thanks for all your help

Mar 19, 2007 | 10:45 PM

Mil1ion

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If either of the battery cables have been remopved while the engine is running..the alternator may have been killed.

This is a common problem with backyard mechanics that think generators are the same as alternators and end up detroying alternators.

Good luck... we're here for you.