Los_Control Posted September 21 Author Report Share Posted September 21 Well, what I'm seeing is pretty much the same issue .... yeah it is temperamental to start because it has been sitting for 7 months without running .... and a few months before that rarely started. .... So lets say it does start but I can not keep it running. Now I think I'm learning that the proper way to wire a ballast resistor is with 2 wires coming from the ignition switch. 1 wire from the start position straight straight to the distributor .... one wire from the run position ..... The idea is to get 12 volts to start the engine. When you release the key to the run position it then runs off of the ballast resistor. Also I have seen that 6.5 while not running is normal .... if it is running, it will vary between 8-9 volts. Voltage will vary depending on heat of the coil. Right now I'm wondering if it is my wiring that is the issue .... I do not have a start position on the ignition switch .... just on/off with a stomp starter. So it is straight 1 single wire coming from switch to ballast resistor .... The ignition wants to see 12v to start then run off of 6v. Mine is never seeing 12v .... this is where I need to spend some time I think. Quote Link to comment Share on other sites More sharing options...
David A. Posted September 21 Report Share Posted September 21 If I’m seeing things right, your picture shows you are using a 12 volt coil. So why are you trying to drop your supply voltage down to 6 volts? Quote Link to comment Share on other sites More sharing options...
Los_Control Posted September 21 Author Report Share Posted September 21 3 minutes ago, David A. said: If I’m seeing things right, your picture shows you are using a 12 volt coil. So why are you trying to drop your supply voltage down to 6 volts? Because thats the way it's done! I'm just trying to convert to 12V using basic 1960's Mopar parts so they are relatively easy to get. Ford and GM did the same thing very early on, then they switched to a starter solenoid and the resistor was built into it eliminating the resistor on the firewall. Same time I'm still using a stock distributor with stock points, they were not use to seeing 12V ..... they will burn out. So Chrysler stayed with the ceramic resistor and the others moved it into the solenoid. ..... they all ran off of 6v at the points. they all had a 2 position switch though .... so I dunno. Right about now, I'm thinking a 318 V8 swap will give me the 2 position ignition switch I need to make this work Quote Link to comment Share on other sites More sharing options...
David A. Posted September 21 Report Share Posted September 21 If you’re going to send 6 volts to your coil, you need to be using a 6 volt coil. Otherwise you will have a very weak spark at your plugs. I would think it would be weak enough that it could cause problems running. Quote Link to comment Share on other sites More sharing options...
kencombs Posted September 21 Report Share Posted September 21 (edited) I always use a Ford starter relay (solenoid) in cases like this. They have an ignition post specifically to send full voltage to the coil when powering the starter. Not applicable if using the stomp starter, but I always change to a bendix style. GM used ceramic resistors on some models but a lot of them had a resistor wire from the ign terminal of the switch to the coil. And then a terminal on the starter solenoid to feed the coil while cranking. Edited September 21 by kencombs Quote Link to comment Share on other sites More sharing options...
kencombs Posted September 21 Report Share Posted September 21 4 hours ago, lostviking said: 6.5V seems a bit low to me. I'm used to seeing 8-9V. Probably due to a mismatch between the generic 12v, that requires a resistor coil, and the value of the resistor chosen. They must be matched in order to arrive at the design voltage. Quote Link to comment Share on other sites More sharing options...
Dave72dt Posted September 21 Report Share Posted September 21 What's your battery voltage while cranking the engine over? I had been taught that 8-9 volts out of the coil on a 12 v system, engine running was normal, that the starter would typically drop available voltage about 3 volts. Systems would bypass the resistor for starting purposes. Feeding it though the resistor plus starter voltage drop would put it at about 6-7 volts out of the coil. Quote Link to comment Share on other sites More sharing options...
Los_Control Posted September 21 Author Report Share Posted September 21 12 hours ago, Dave72dt said: What's your battery voltage while cranking the engine over? yes it is different when cranking, 9.8V ..... I just put a fresh set of plugs in it and it almost started. Been awhile since I worked on the truck, remembering awhile back I remember having a problem with the carburetor .... thinking it was clogged up somewhere. So I disconnected the linkage and ready to pull it and go through it ..... after I mow the lawn. I can pour fuel straight into carb and makes no difference .... I know the timing is good enough to run .... so I still think it is spark related. I just want to eliminate the possible carb issue. 14 hours ago, kencombs said: Probably due to a mismatch between the generic 12v, that requires a resistor coil, and the value of the resistor chosen. They must be matched in order to arrive at the design voltage. FWIW, I ordered from rockauto the coil, ballast resister together for a 1961 Dodge truck with a /6 .... so they should be matched. I just need to do better research, I thought this combo would work .... kinda a no brainer type deal. Trying to figure out my best way to correct it. Quote Link to comment Share on other sites More sharing options...
kencombs Posted September 21 Report Share Posted September 21 (edited) 25 minutes ago, Los_Control said: FWIW, I ordered from rockauto the coil, ballast resister together for a 1961 Dodge truck with a /6 .... so they should be matched. I just need to do better research, I thought this combo would work .... kinda a no brainer type deal. Trying to figure out my best way to correct it. In general aftermarket coils and such are approximate fit to literally hundreds of makes/models/years. But may not be specific for a singe fitment. Close enough to work for most if not all. Ballast resistors are fairly wide ranging in value. I copied this chart off the net. Typically the coil and resistor combo is selected to limit current across the points to 4 amps or less. That's real real goal. the way I do a static test of the workings is to turn on the ignition, turn the engine so the points are open, hold the end of the coil wire near a ground on the engine. Closing the points by bridging the gap with a screwdriver and then removing should create a spark to jump the gap. And it should happen with or without the condenser IF the condenser shorted internally. Just create a path for current to flow and break it. Should spark when broken. Edited September 21 by kencombs Quote Link to comment Share on other sites More sharing options...
Dave72dt Posted September 21 Report Share Posted September 21 Take an ohm reading across the two small posts of your coil. That's your primary coil resistance. and the number you need for matching the farad rating of your condenser You can do the same across each post of your resistor to get it's ohm reading. You can Google the process for testing the farad rating of your condenser and from there to match the system properly. Quote Link to comment Share on other sites More sharing options...
Los_Control Posted September 26 Author Report Share Posted September 26 Well I went through the carburetor and am pleased with it .... has a really good strong stream from accelerator pump now. Fuel is not a issue. I pulled the distributor out and installed the original good working condenser, then put the distributor back in and still no start. Slept on it and in the morning I hooked up my spark tester on a spark plug and this time I had no spark to the plugs. So I check voltage and trace spark going to the distributor, remove cap and no spark when turning over but the arm of the points does have voltage going to it. I did file and then clean the points before installing distributor. So I pull the distributor out and on the bench I connect power to the screw and ground to the body with the points open. When I rotated the distributor the points caught fire .... literally had a 2" flame coming off of the spring tension that connects to the power. So my distributor seems to have a ground issue and is direct to ground when it rotates. ..... Installed it seems the engine block is taking the current .... on the bench the points got the brunt of it. Everything is installed just how it has always been ... I removed the condenser wire just to get it out of the way for photo. Now I'm blaming it on the distributor, it started to fail and gradually got worse and now it will not run at all. I guess I could disassemble it and see where the insulator failed .... how the current is being transferred to ground. And fix it. One reason for switching to 12V was to do the /6 distributor conversion sooner or later .... I just got off the phone and have a used one being shipped from a wrecking yard in NM -> TX $47 total with shipping. So I'm not going to spend anymore time trying to correct the current problem, just move onto the conversion and hope that works out. Quote Link to comment Share on other sites More sharing options...
lostviking Posted September 26 Report Share Posted September 26 I know you said you were moving on, but... Put a small insulator (thick paper?) between the points. Is the screw where the wire attaches to the distributor shorted to the case? If not, measure the condenser lead to the case. One of the two is the problem. If the insulator going through the dist wall is damaged, you could have a short. If the screw on the inside is touching, you will have a short. If the condenser is shorted... There are only a couple things in the picture that could cause a short. Quote Link to comment Share on other sites More sharing options...
Los_Control Posted September 26 Author Report Share Posted September 26 53 minutes ago, lostviking said: I know you said you were moving on, but... Put a small insulator (thick paper?) between the points. Is the screw where the wire attaches to the distributor shorted to the case? If not, measure the condenser lead to the case. One of the two is the problem. If the insulator going through the dist wall is damaged, you could have a short. If the screw on the inside is touching, you will have a short. If the condenser is shorted... There are only a couple things in the picture that could cause a short. I know you are correct, it really only can be a few things ..... In my simple mind, I call this getting lost in the weeds. I have already spent too much time on diagnosing the problem .... I'm thankful it finally got bad enough I can actually find it, not sometimes it works, sometimes not. I feel like when I get around to the conversion and disassemble the distributor .... I will get a AH HA moment, thats where the problem was. Where I'm at in my build is this. I have always saved the interior for last .... least important. .... I installed my freshly cleaned carburetor and can not connect my new choke cable or throttle cable. I did modify the seats to make them work .... the base is removable from the cab and have a flat surface to lie down and work .... I created a workable gas pedal I worked on the clutch pedal .... I have done some work here, now it all needs to be stripped out and prepped and painted. ..... This is where I should be spending my time. Thats what I mean by getting lost in the weeds .....I spent 2 weeks on a non run issue that I know I can fix, and nothing productive has been done on the truck. I got a good month or 6 weeks of painting weather ahead .... I'm playing with a distributor .... time to get out of the weeds. Quote Link to comment Share on other sites More sharing options...
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