Electrical Help Needed - Big Time

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Sport 360

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OK, so I started the car today, luckly with the hood open, and noticed some wisps of smoke coming off the red, fusible link wire from the relay that goes into the fire wall. The attached picture shows the rather bad predicament I'm in now.
The battery read 12.5 V off and 19.2 V running. The Amp meter on the dash is way up to the maximun (+40) at any RPM other than idle. This is what I was investigating when I noticed the smoke.
The battery is brand new as is the voltage regulator.

Any ideas of where to look ??

All help is greatly appreciated, the weekend is coming and I need to get out there !!
 

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I'm not an expert but, if there is still a short would the alt be putting out more voltage to compensate? Start by pulling fuses one by one to see which one is shorting.
 
Check your alt. and its wiring. If the regulator is known good (my prime suspect really) it will have to be the alt. or the wires to it. You have the isolated field alt (1970 and up) and if one of the two field wires are shorted to ground you will have full output all the time from the alt. And after you find the problem you will need to replace the burnt wires in the photo. Remember just because its"new" does not mean its good.
 
If I remember correctly, that wire is the main power feed to the fuse box isn't it ??
 
I'm not an expert but, if there is still a short would the alt be putting out more voltage to compensate? Start by pulling fuses one by one to see which one is shorting.

If there is a short in the cars wires the alt. will not put out more voltage-its regulated at 14.5 volts or so. It should never go higher that that.
 
Check your alt. and its wiring. If the regulator is known good (my prime suspect really) it will have to be the alt. or the wires to it. You have the isolated field alt (1970 and up) and if one of the two field wires are shorted to ground you will have full output all the time from the alt. And after you find the problem you will need to replace the burnt wires in the photo. Remember just because its"new" does not mean its good.

If I disconnect one or both of the field wires, would that give an indication of the issue ?
 
I'd say that somewhere in your charging system one of your wires between your alternator and the Voltage Regulator, a wire is grounded - could be a wire has become bare because it was rubbing on something and is hitting bare metal causing that part of the Voltage Regulator to see ground or 0 volts and put the alternator at full charge. I had this happen after I had upgraded my charging system to the solid state voltage regulator and a 2 field alternator. Once I taped up the offending wire and re-routed it, all was good. My wire had rubbed itself on the bracked I made for my coil where the wire went behind the coil and across the back side of the engine to the Voltage Regulator. However, I don't think my fusible link was smoking, so maybe your trouble is somewhere else. Hope this helps.
 
I'd say that somewhere in your charging system one of your wires between your alternator and the Voltage Regulator, a wire is grounded - could be a wire has become bare because it was rubbing on something and is hitting bare metal causing that part of the Voltage Regulator to see ground or 0 volts and put the alternator at full charge. I had this happen after I had upgraded my charging system to the solid state voltage regulator and a 2 field alternator. Once I taped up the offending wire and re-routed it, all was good. My wire had rubbed itself on the bracked I made for my coil where the wire went behind the coil and across the back side of the engine to the Voltage Regulator. However, I don't think my fusible link was smoking, so maybe your trouble is somewhere else. Hope this helps.

If the 2 field wires are mixed up would that cause an issue ??
 
If I remember correctly, that wire is the main power feed to the fuse box isn't it ??
Yes and what happened is with too much current being put out by the alt. and the over load caused by it and add in the corrosion at the fuse link plug you get heat. Too much heat and you get melting/burning. You may want to clean your bulk head connectors after you find out what is going on with you alt.
 
If I disconnect one or both of the field wires, would that give an indication of the issue ?

At best-maybe. But you may have a broken brush holder in the alt. that is grounding out one side of the field and causing your problem. You need to get your multi-meter out and take readings (ohm it out with the cars battery disconnected).
 
At best-maybe. But you may have a broken brush holder in the alt. that is grounding out one side of the field and causing your problem. You need to get your multi-meter out and take readings (ohm it out with the cars battery disconnected).

Don't want to seem too useless here, I do have a mutimeter but I'm unsure of the testing procedure. Is it between the field points and the main output ?? If so, what should the reading be ??
 
"Started the car today" unquote.
So what work has been done since the last time it ran ?
 
"Started the car today" unquote.
So what work has been done since the last time it ran ?

Nothing has changed, car has only been running for a week or so. The dash gauge has been high the whole time but this smoke is new to me.
I have driven about 30 miles so far, just a few at a time with no problems, trying to make the distance "comfort circle" a little larger each time LOL.
Runs great other than that.
 
Don't want to seem too useless here, I do have a mutimeter but I'm unsure of the testing procedure. Is it between the field points and the main output ?? If so, what should the reading be ??
Unplug the wires to the voltage regulator. Now check each wire (in the harness) to ground-use the ohms scale. You should get no readings. If ether wire shows a reading you will need to unplug the wires at the alt. and recheck the wires to ground. If you get no readings now you will need to check the alt. Check each tab(were the wires plug in) to ground. If you get a reading now you have a bad brush holder or bad alt. remove the brush holders (they are plastic and held on by a screw)The brush holders come with the brushes on them-they are held on by a phillips screw. You can get new ones at the stores and they are cheap.
 
I assume you have everything connected properly. Definitely a short somewhere. The fusible link is/was doing exactly what it should do.
A short in the ignition switch, feeds to the fuse box, headlights, etc.. would cause it. All those larger gauge wires beyond that link.
Anything that is fused at the fuse box would or should blow that fuse rather than blowing the fusible link.
 
Unplug the wires to the voltage regulator. Now check each wire (in the harness) to ground-use the ohms scale. You should get no readings. If ether wire shows a reading you will need to unplug the wires at the alt. and recheck the wires to ground. If you get no readings now you will need to check the alt. Check each tab(were the wires plug in) to ground. If you get a reading now you have a bad brush holder or bad alt. remove the brush holders (they are plastic and held on by a screw)The brush holders come with the brushes on them-they are held on by a phillips screw. You can get new ones at the stores and they are cheap.

Ok, sounds easy enough. I'll give it a try.
Thanks a million, I'll let you know how it works out. :love4: (not that way, LOL)
 
Either your voltage regulator doesn't (regulate voltage), or it isn't able to due to a field signal wire being shorted to ground. This could be either within the harness or internal to the alternator. In either case, a grounded field will cause the alternator to produce maximum output all the time.

As stated above, remove ONE of the field wires from the alternator and test the system. If no change, reconnect that wire and disconnect the other. If no change, you have a short that is common to both, likely within the alternator. A new regulator is cheap, so you might want to start there.

Also, note that you DID NOT fry the fusible link. The connections overheated due to resistance within them. Once you solve your problem you should inspect and clean both this connection as well as the bulkhead connector.
 
If it's putting out 19 volts you should not run it until you fix the problem or at least pull the field wire to the alternator till you find the problem. It very well could be the regulator so start there. Let us know what you find.
 
You can troubleshoot this easy

Start the car, alternator hooked up, and diddle with the idle screw until the charging voltage is around 13-15. You want it high enough to troubleshoot, low enough to "not hurt" the system/ battery

Pull one field wire off at a time, and make sure that EACH time you do this, it quits charging. Switch the field wires at the alternator and repeat. If this is OK, the wiring is probably OK. It would not hurt to pull the connectror off the regulator and make sure THAT stops it from charging. If that's OK.......

Now stick one probe of your meter directly onto the battery negative post, the other probe directly onto the regulator case. Make sure you "stab" it into metal. You are looking for a VERY low reading, zero is perfect, you don't want over .2V (two tenths of a volt) Higher voltage means the regulator is NOT seeing the battery ground.

If this is OK, check the hot side. Stab one probe directly onto the battery positive post, the other probe as close as you can to the regulator IGN terminal. Probably the key side of the ballast resistor is OK, (dark blue.) Once again, you are looking for a very low reading.

If all the above checks out, and the battery is OK, replace the regulator.
 
I assume it is "old ammeter". What was it reading? Start it and grab the back of it and see if it is hot. Bad connection, bad gauge. bad been there, so voltage meter now, bypassed those bulkhead wires.
 
OK, so it is fixed !!! :toothy7:

Thanks so much to everyones help, it sure helped me find the problem.
It turned out to ba a bad splice in one of the wires from the regulator. The wire to the alternator was fine, the other one had been spliced sometime in the past (before I owned it) and had come apart causing the alternator to charge fully. Such an easy troubleshoot when its expalined what to look for and you use a mutimeter.

Thanks again to everyone for the help.............now, if only someone could come up with a way to make the the lifters/rockers more quiet :banghead:
 
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