Author Topic: engine wiring, alternator  (Read 2344 times)

Offline angeloscuda

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engine wiring, alternator
« on: February 05, 2004 - 10:03:02 pm »
I'm having problems with my charging system on my car; so far i have changed my alternator 3 times, changed the battery,the battery cables, the starter relay, the module, and the voltage regulator. I am a autobody tech. but the concept of automotive electricity has always eluded me. Now; i have changed all these parts within the last 4 months and i'm still not making any progress. Are there any automotive electricians out there? If so here are the symptoms; yesterday i was driving the cuda and when i turned on the headlights the car staled, the alternator is new and it's the one with the 2 field connectors and the positive lead, the engine is a slant 6 with a automatic for now. I bought the car from another Mopar nut who is building a demon racecar so the history of the car is a mistory; as far as if the parts are the original ones that came with the car or not, as far as the style of alternator ( 1 or 2 wire type) so i replaced the same style one that was on there. any help would be greatly appreciated.  thanks???


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Re:engine wiring, alternator
« Reply #1 on: February 05, 2004 - 10:29:32 pm »

Gosh... got me stumpted (sp?)...

« Last Edit: February 05, 2004 - 10:30:34 pm by lemonboy69 »

Offline 4Cruizn

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Re:engine wiring, alternator
« Reply #2 on: February 05, 2004 - 11:05:54 pm »
Now I'm no expert and I'm sure Chryco will probably be better at this than me but . . .if I had to guess, I would say that either you have a bad ground or your new voltage regulator is bad.   8)

Offline DodgeFreak

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Re:engine wiring, alternator
« Reply #3 on: February 05, 2004 - 11:31:06 pm »
i don't know what your problem is for sure...but just to go along with 4cruzin....just because you buy a electrical part new doesn't always mean it will work...they have been bad out of the box before...but you probably knew that already....
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Offline MEK-Dangerfield

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Re:engine wiring, alternator
« Reply #4 on: February 06, 2004 - 04:33:43 am »
How about some more info. Like, is it charging while it's running? If so, then I'm stumped too. If not, then we can look at each component one at a time. I've been burned buying a dead "new" voltage regulator before. Also make sure it is making a good ground contact with the firewall.



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Offline 74chall

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Re:engine wiring, alternator
« Reply #5 on: February 06, 2004 - 08:35:11 am »
How bout the ballast resistor?  It might not be the charging system but the power wire to the coil which goes to the bulk head on the fire wall. We need more information, i think i will be able to help you out.

Offline Autophile

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Re:engine wiring, alternator
« Reply #6 on: February 06, 2004 - 11:37:15 pm »
You might have corrosion on the wiring connectors in the wiring bulkhead (where the wires pass through the firewall). The big red power wire that passes through the bulkhead is notorious for giving problems on E-bodies and 71+ B-bodies. One problem with the big red power wire is, often someone will replace the alternator with a higher output unit, which overloads the wire at the bulkhead, which leads to hair loss problems down the road....

I have had problems in the past with burning up the alternator field wires too. I suspect that is the primary problem in your case. The only way to fix them is to trace them and replace them, if one or both is showing excessive resistance.

Also, the voltage regulator is a regular PITA when you have a high output ignition. To solve all problems (regulator, field wires, and power wire), I bought a PowerMaster one-wire high output alternator and ran the alternator single wire directly to the battery. Now, I have lots of juice, all the time.

One other thing to check is the ground wires. You need a good ground from the battery to the frame, and from the block to the frame. Make sure you have clean contact with bare metal on each end of the ground cables, and use fatty cable.

Hope this helps.
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Offline oldvamoparfan

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Re:engine wiring, alternator
« Reply #7 on: February 07, 2004 - 12:11:54 am »
You may have already checked this, but chk for a loss of ground strap between the engine & the firewall.  A freind of mine had the same problem after he chgd the engine in his Dodge PU.  He didn't reconn the eng to firewall ground.  I ckd w/ volt meter & saw about 2.5 volts drop.  This drop to the ignition module would drop voltage to the spark plug approx 5000 volts.  Add this to the approx 4 volts dropped by the ignition resistor, & you dont have enough juice to fire the plugs.  This would be further compounded as more accessories are turned on. (Drop between bat ground & dash or firewall grounded electronics would increase)  There are other things that might cause this, but this is  the easiest to fix, or at least try.  Just run a wire ( maybe 12 ga) from bat ground directly to good clean ground on firewall.   Hope this helps.  Ovmf
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Offline Chryco Psycho

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Re:engine wiring, alternator
« Reply #8 on: February 08, 2004 - 12:06:52 am »
What year is the Cuda & which system are you using , points or eletronic regulator & 1 or 2 field wires ?
 definatly check & clean the connections at the firewall & ammeter

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