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Hey all. So I've been having electrical issues with my Dart (225 slant six) for the past couple of weeks now. Main problems include flickering of the headlights and domelight and the radio cutting off and on intermittently while driving. When revving the engine, the flickering actually worsens to a point and then the lights steady themselves. Once power is reduced, the lights (including dash lights) dim until I give it more gas.

My dad and I weren't exactly sure what the source of the problem was, so we replaced pretty much everything: new alternator and belts, new battery, new voltage regulator. The timing and idle have been adjusted to recommended specs. Now, when we checked the new voltage regulator, it would click on and off incessantly when accelerating, so we thought that we got a bad one and bought another one. After installing the new new one, we have the same problem. We read about voltage regulators not being grounded well enough, so we ran its own grounding wire to the negative post of the battery. We're really not sure what it could be at this point, so any suggestions would be appreciated.
 

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Bad ignition switch or intermittently bad connection at the big firewall connector, or bad connection at the ammeter.

And with any charging issue, you should measure the voltage at idle and when revved.
 
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Bad ignition switch or intermittently bad connection at the big firewall connector, or bad connection at the ammeter.

And with any charging issue, you should measure the voltage at idle and when revved.
Thanks for the answer Bob, my dad was thinking the same things as well. Now I just gotta find a way to get a good wiring diagram without paying $20, hahaha.
 

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Every electrical issue I had on my A body Darts and Valiants was from corrosion at the bulkhead connector at the firewall.
But Bob has listed some other good things to check too.
 
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Always disconnect a battery terminal first. I've had good luck with the older ignition switches. The firewall connector and ammeter nuts should be checked for corrosion or discoloration. Remember that the ammeter wires are always 'hot'.
 

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Always disconnect a battery terminal first. I've had good luck with the older ignition switches. The firewall connector and ammeter nuts should be checked for corrosion or discoloration. Remember that the ammeter wires are always 'hot'.
Remember to disconnect NEGATIVE post/cable first so if a wrench happens to touch any other ground adjacent to battery post, nothing will happen - unlike what will happen if one end of wrench is on POSITIVE post and other end touches a ground.
As Bob noted, make sure wires to ammeter are 'tight' - but do not turn any of the nuts while allowing the wire loops to twist as well - otherwise internal damage to unit is likely. Hold each wire loop stationary before attempting to turn any of the nuts. Sometimes it's the INNER nuts that are loose so if that is the case, loosen the outer nut first and then (gently) tighten inner nut and then re-tighten outer nut.
On my '77 P.W., one of the inner nuts came loose and that caused ALL kinds of 'gremlins' - from erratic idle and timing to flashing lights and, ultimately, heat and even smoke coming from one or more big wires under dash. Yikes! Good luck and I hope it is not serious.
 

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As far as the ammeter gauge goes, be careful, if the insulation between the case/housing and the bottom nut is bad, it will short out and melt every single wire in the car since direct 12+ volts goes to the gauge before it goes to the fuse block and over time the insulating material can and does break down. I think they used phenolic material which becomes brittle and breaks easily. Ignition switch is not as common, but it is an easy check, the plug should simply disconnect, two tabs hold it to the ignition switch. Voltage regulator clicking is an indication of a change in voltage (Duuh), but, check the wires to the tail lights, as in the wires not touching the metal frames that hold the bulbs, cracked wires, things like that. I had my whole dash wiring overheat and short circuit because someone decided to "borrow" a tail light bulb and the wire end touched metal and shorted things out, only found it when replacing the dash harness and thought it was funny the connection to the tail light harness was kind of heat/melt damaged and located the problem.
 
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