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Ignition Problems

oldfolksmopar

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I am in need of some help. I have my 1980 Dodge D150. 318 - 4 speed with air. This has been going on for months. When I start it up in the morning I notice that the alternator is not charging and the tac is jumping all over the place. So I shut it off and bingo. I try to start it and it has nothing. Not a single light or anything works. The truck is dead. I checked the battery and it is fully charged. But nothing, no juice. So I start fiddling with turning on and off the headlights, the A/C switch. I am just flipping them on and off. Then magically, by doing this all the sudden I have power again. Sometimes it take only a few minutes and then like yesterday it took me over an hour before it came to life. I have checked every connection possible. Nothing is loose.

It has done this on several occasions. I can go somewhere when everything is working correctly and when I come back out to start it up, it will start. however I notice again that something is not exciting the alternator. So I shut it off and then it is dead again, nothing. IT may take me several minutes to many many minute with fiddling with the lightswitch and other components and bingo, it has power again. Sometime when I get it started after this it still is not charging. I'm thinking it is one of the fusable links that I can not find that may be malfunctioning. I don't think it is the light switch either.

Guys I have to get this fixed. Any information will be greatly appreciated.
 

AJ.

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the lightswitch is totally independent of the ignition system; the two have nothing in common, except the battery.

The totally dead system, points to the main power supply to the ignition switch;
But since the lights are also affected, it more or less points to the battery or it's connections. Clean and tighten the cables, both ends, and see what happens. If you have a load-tester, give it a workout. If you have a hygrometer, test every cell, looking for 2.2 volts .
The dancing tach could be because the ignition system is intermittently shutting down, as in losing power.
The fly in the ointment here is the ammeter. on one side it receives battery power. On the other it receives alternator power. So once the engine is running, with a good working charging system, you can remove the battery and the truck will continue to run.
Therefore; in your case, I would check the back of the Ammeter and prove the connections are tight. And not just tight on the studs, but also tight on the copper bar. I made that mistake once and it cost me a lotta lotta time.
Good luck
 

oldfolksmopar

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Location
Speedway, IN
the lightswitch is totally independent of the ignition system; the two have nothing in common, except the battery.

The totally dead system, points to the main power supply to the ignition switch;
But since the lights are also affected, it more or less points to the battery or it's connections. Clean and tighten the cables, both ends, and see what happens. If you have a load-tester, give it a workout. If you have a hygrometer, test every cell, looking for 2.2 volts .
The dancing tach could be because the ignition system is intermittently shutting down, as in losing power.
The fly in the ointment here is the ammeter. on one side it receives battery power. On the other it receives alternator power. So once the engine is running, with a good working charging system, you can remove the battery and the truck will continue to run.
Therefore; in your case, I would check the back of the Ammeter and prove the connections are tight. And not just tight on the studs, but also tight on the copper bar. I made that mistake once and it cost me a lotta lotta time.
Good luck
Thanks AJ for the info. I think you are correct about the ammeter. Everything else checks out. I may have a problem with that. I have plenty of power to everything including the starter relay. nothing beyond that. When it goes dead, it is dead. no power anywhere. I think today I will be taking the dash apart to test everything and check those connections. Many thanks again.
 

oldfolksmopar

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Location
Speedway, IN
I had same issues with '77 Power Wagon decade ago. It was loose connections on Ammeter.
Well I think you and AJ are on the right track. I took the dash apart and found the connection on the ammeter not loose as far as the wires go, but took them off and the nut that is holding close to the gauge itself were kind of loose. I tightened them both and then connected the wires back up. So far it is working like a charm guys.

It has done this before so we will see as I drive it or if I have continued problems. time will tell. So far it has been starting and charging every time. Thanks for all the support from everyone. I will let you know in a week or 2 ow it is going. Thanks Larry
 
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