too much voltage after adding headlight relays

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I live in Rockvale at the edge of Murfreesboro towards Franklin.

If I was looking for a switch, I would look for a new old original on ebay.

It is also possible to wire in a relay so the coil is fed from the IGN circuit, and main contact powered from battery. That solves the problem, and takes load off the switch. Similar can be done to serve other loads.

The bypass 67Dart273 suggests, including bulkhead repair helps too.
 
Factory wiring?

Where did you pull power for the headlights?

If the answer to the first question is Yes, and the power is from the starter relay... that's a BAD place to pull power.
 
Is there any way you can give me a step by step on the relay install so I can do that and replace the ignition I don't want it to do this on the drive back to tn
 
I think we need the answer to #27 first. If headlight relay power contact is fed from ignition, that is a problem. Just wondering, because problem started with adding that.
 
that's where its coming from. just read cracked post from his kit he sells, so the 12v should come from the alternator output? and its not original wiring I ran all new from the relays to the headlights
HeadlightRelayWiring.gif
 
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Well I tried the relay idea to the best of my knowledge I did 12 volts from the battery to terminal 30, grounded terminal 85 at the windshield wiper motor stud, terminal 86 used the blue wire coming out of the firewall ( top passenger side wire on the middle plug) I think it's the voltage return for the ignition switch at the factory splice. I ran the other 2 wires from the splice to terminal 87. When I turn the key to the run position and pull off the blue field wire I have the same voltage as the battery. But if I plug the field wire in it drops 2volts. I need to get this fixed over this weekend so any help is needed and greatly appreciated I'll try and troubleshoot and respond as quickly as possible.thanks for your patience also I know this has to be annoying to explain
 
I really have a hard time following verbal connections on a car I cannot see. A schematic is worth 1000 words. The intent of adding the relay is to power pin 30 from battery, and I assume #12 gauge wire will minimize voltage drop. Then pin 87 should power directly, to regulator, ignition coil (blue)feed via ballast and field. The ignition blue that used to power all that, is cut free, and powers pin only pin 86, relay coil. When I write directly on pin 87, that means do not do that under dash, do it under hood. That way it does not go thru the bulkhead connector. On an early car it is easy, it can be done without a cut, by pulling connectors from ballast, and regulator, use one to supply pin 86, then make new wiring to regulator, and ballast fed from 87. I am not sure on newer car, with different regulator system. Others like Del, crackedback may know best way to directly splice in to later regulator circuit wiring.

The field current should only be 3 to 5 amps. If it is greater than that, there is likely a shorted turn in the field. Time to get alternator tested. It the field is nornal, the existing wiring, and or bulkhead connections are poor, resulting in the 2V drop. The suggested wiring gets around that on the pin 87 feed you wire under hood.

While this may get the car to run and charge, there are likely other bulkhead connections that need to be repaired. If the ignition one gets much worse, it may even fail to power the relay coil that is only about 0.1A.
 
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So I need to make my pin 87 connection after the ballast resistor? I think that is where I messed up on the bypass. Also when I have the blue field wire connected to the alternator and I pull the green one with the key in the run position I have .5v I'm not sure if this helps or not
 
I can not follow what you write about ballast wiring, and what you might have done.

I do know wiring field directly to alternator stud is bad idea, it prevents turn off if regulator fails shorted.

I think at this point it is best to get professional help, in your local area. Or rent car, or fly.
 
I'm pretty sure I have the relay installed correctly because my voltage at the blue field terminal with the key in the run position is the same as the battery which meant that I now have no voltage drop from the harness so I just need to get my alternator checked out and I'll go from there. Thanks for trying to help me out lol
 
You are welcome. Good luck on your trip.

The fix does not help the accessory loads on ignition switch. So the weak bulkhead feeds may keep those from working well. Very hot and humid here in TN. Also rain, most every day. So A/C and wipers important. Be safe.
 
KitCarlson said:
You are welcome. Good luck on your trip.

The fix does not help the accessory loads on ignition switch. So the weak bulkhead feeds may keep those from working well. Very hot and humid here in TN. Also rain, most every day. So A/C and wipers important. Be safe.
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I don't mean to thread hijack, but how would one go about adding a relay to the ignition switch, to take that load off it?
 
plumkrazee70 said:
I don't mean to thread hijack, but how would one go about adding a relay to the ignition switch, to take that load off it?
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If you YouTube how a 4pin relay works and study the diagram it will help a ton that's what I did and just tried it outo and it seems to be working. I just have other issues now
 
hobbsza said:
If you YouTube how a 4pin relay works and study the diagram it will help a ton that's what I did and just tried it outo and it seems to be working. I just have other issues now
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Great. Thank you!

The interesting thing about Mopar wiring is the welded splice. I have already done the ammeter bypass, so I will look into taking the load off the ignition switch. I think I may have an idea, while I type this. lol.
 
Beware that that you cannot connect the relay coil 86 pin to the pin 87. The coil must be separate from the load side of relay, or once it is started, it will not turn off. Only the ignition key wire goes pin 86, the loads that were fed by that, are now fed by the pin 87.
 
I used the blue wire coming frome the bulkhead connector (engine bay side)for terminal 86 to trigger the relay. the other 2 blue wires that were spliced to that one wire are now on terminal 87 so I believe I did that part correct. I'm installing a new ignition switch and leaving the relay setup on. I will see where that gets me lol
 
i just cant figure out why I lose the 2v with the blue field terminal connected but when I disconnect it from the alternator the voltage comes back up to match the battery voltage.

and when I have the alternator completely hooked up it is giving me 10.6v at the blue field wire and I disconnected the VR to check the voltage at the plug and it comes back up to 12.6 at the field terminal and the VR plug which matches my battery. I made all of these reading with key in the run position
 
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I am not sure if your readings are done with engine running. I am guessing not.
I tried to suggest that you measure the field current draw. Measure current by selecting high amp range 10 to 20 A, if your meter has that, it also takes plugging into correct terminals on meter. Then place meter in series with field. A good reading is 3-5 A I assume you know one field wire gets powered with the ignition "on", the other is pulled low (to ground) by the regulator as necessary to make the voltage correct. The regulator case must be grounded to work. It is easy to measure the voltage regulator case to chassis, battery (-), and engine, with engine running. The good readings are near zero. Remember to set the meter and terminal lead sockets correctly. Measuring volts on current setting will blow meter fuse.

Voltage drops are caused by current passing thru resistance. Volts is current times resistance. The voltage drop, may be the drop in the battery voltage as the field draws current. Batteries have internal resistance that increases with discharge. Measure at battery terminal when you connect field, if voltage is the same with the two volt drop, then it is a weak battery assuming the field current is correct.
 
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just out of curiosity is there any way my ignition box could be causing this issue it has a ton of sap looking sticky crap oozing out of it.

when I measure the amperage of the field in "series" where exactly should probe? just the blue field wire? I understand series means along the same electrical path I just want to make sure I'm doing everything correctly
 
The meter is used to complete the circuit. One lead to disconnected field wire, the other to terminal where it goes. Danger! The field is inductive, releasing the current, with fingers on metal probe tips will bite you with hundreds of volts.

There are clamp-on meters with Hall sensors. Much easier to use, just clamp around wire.
 
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