Plymouthy Adams Posted November 15, 2011 Report Share Posted November 15, 2011 Robert, can you post that drawing...my book only goes to 55..that would be a funky position for the resisitor in the circuit..the normal path in all cases I have ever seen has had the power from the run side of the ign sw to the +/- (depending on pos/neg gnd) terminal of the reisistor and the other side to the power terminal of the coil...the terminal from the other primary pole of the coil goes to the points and on to ground when the points close completing the circuit..the seconday side fires when points open and collaspe the field.. the start circuit of the ignition switch will place 12 volts on the input of the coil/far side of the resistor block either connection is appropriate.. Quote Link to comment Share on other sites More sharing options...
55 Fargo Posted November 15, 2011 Author Report Share Posted November 15, 2011 Just installed an Interstate 12 volt battery. cranked over engine without ignition circuit on, man does 12 volt crank over nice, is faster than 6 volt, that is for sure. The oil pressure started to come up on gauge, and when I did turn key to on, got a slight discharge showing on ammeter , so that must be wired okay. Got help coming over tonight, going to she if the old girl will fire up, and start..... Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted November 15, 2011 Report Share Posted November 15, 2011 Tim; See posting #11 in this thread. I downloaded the drawing so I could blow it up to better read it. It does appear that the resistor is plumbed in between the coil and the points. Strange? Quote Link to comment Share on other sites More sharing options...
Robert Horne Posted November 15, 2011 Report Share Posted November 15, 2011 This is the diagram from post #11. Quote Link to comment Share on other sites More sharing options...
Robert Horne Posted November 15, 2011 Report Share Posted November 15, 2011 This diagram is from the Power-Wagon people. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted November 15, 2011 Report Share Posted November 15, 2011 (edited) while that configuraton is strange..it is still the same basic circuit for we are dealing with resistance in series, the current draw will be the same either way....I believe GM did this also and maybe others in the first years of conversion...why is anyone's guess.. I will not use this method but instead the resistor before coil and not resistor after.. Edited November 15, 2011 by Tim Adams Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted November 15, 2011 Report Share Posted November 15, 2011 This diagram is from the Power-Wagon people. This drawing looks correct if I am reading it right. It appears the purple wire is the 12 volt by-pass. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted November 15, 2011 Report Share Posted November 15, 2011 ok the why of the earlier style ballast between the coil and the distributor..and yes it is heat related in this application...as the resistor is secondary in the circuit and the resisitor is cold more voltage does flow through the coil for the "hotter" spark..and as it does heat up by the continued use and flow of current the resistance will change with the heat..once at the operating temperture..the current will be equal (theortically if same reistance as coil) this application was used for a number of years it seems until they went to the other method of applying 12v start to the coil and dropping input before the coil in run position..in operation it works as the later model GM internal resistance coil..I have to admit that I was not familar with the early change overs as most of my time has been spent with pre 55 and mostly mid 60's and up..my bad..but me on the learning curve now.. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted November 16, 2011 Report Share Posted November 16, 2011 as an aside note here, the placing of the resistor between the coil and the distributor requires the application of a "temp sensitive resistor"..do not confuse these with the later style that is fixed value as used on the start on 12 run on 6 by-pass inginiton feeds..if you mix these up and apply a fixed value resistor in lieu of the temp sensitive...you have rendered the ignition system to that of 6 volts at all times... Quote Link to comment Share on other sites More sharing options...
55 Fargo Posted November 16, 2011 Author Report Share Posted November 16, 2011 Tried to start engine tonight, no spark, the old coil is most likely the culprit. The rotor, cap are new and in good condition, points are gapped at .020. and my battery has been run down. Not sure what sequence will trouble shoot, and systematically go through the process of elimination. I have the battery on a charger right now. Good news is the oil pressure was jumping up on the gauge...... Quote Link to comment Share on other sites More sharing options...
55 Fargo Posted November 16, 2011 Author Report Share Posted November 16, 2011 Tried engine this morning, with another coil a 12 volt requiring the ballast resistor, there is power from ignition switch through ballast to the coil. Charged battery over night, primed carb, and she truns over well, but will not fire. I have read all the threads related to a "no start" condition, and hope to figure this out soon. Not sure about the distributor, although it has new points, rotor, condensor, and is in super clean shape, it might have not worked for me some time back, but don't remember for sure. So any ideas??? Quote Link to comment Share on other sites More sharing options...
Jim Yergin Posted November 16, 2011 Report Share Posted November 16, 2011 Fred, Are you sure the distributor is not 180' off? Jim Yergin Quote Link to comment Share on other sites More sharing options...
Robert Horne Posted November 16, 2011 Report Share Posted November 16, 2011 Is the coil firing now? Quote Link to comment Share on other sites More sharing options...
55 Fargo Posted November 16, 2011 Author Report Share Posted November 16, 2011 Fred,Are you sure the distributor is not 180' off? Jim Yergin tried both ways. I have power from ignition to coil, but no power from coil wire to diz, not sure that is correct or not.... Quote Link to comment Share on other sites More sharing options...
suntennis Posted November 16, 2011 Report Share Posted November 16, 2011 When starting, two basic things needed are spark and fuel. If you are having the spark plugs to fire and there is no indication of the engine trying to run, the problem is probably that there is no fuel. If you have both fuel and ignition regardless of timing, the engine should run, backfire thru the carb or afterfire out the exhaust. If you have the plugs firing, are you using any starter spray in the carb to aid the start? For the coil, check the resistance across the primary windings which would be the two small terminals of the coil. If you get 1.4 ohms or so, the circuit is good. If you get unlimited resistance, the circuit is open and the coil is bad. Quote Link to comment Share on other sites More sharing options...
55 Fargo Posted November 16, 2011 Author Report Share Posted November 16, 2011 When starting, two basic things needed are spark and fuel. If you are having the spark plugs to fire and there is no indication of the engine trying to run, the problem is probably that there is no fuel. If you have both fuel and ignition regardless of timing, the engine should run, backfire thru the carb or afterfire out the exhaust. If you have the plugs firing, are you using any starter spray in the carb to aid the start? For the coil, check the resistance across the primary windings which would be the two small terminals of the coil. If you get 1.4 ohms or so, the circuit is good. If you get unlimited resistance, the circuit is open and the coil is bad. thanx coil tests at 2.2 ohms Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted November 16, 2011 Report Share Posted November 16, 2011 2.2 ohms is not a concern, do you know for certain that the meter you are using is calibrated...probably not..expensive process... Quote Link to comment Share on other sites More sharing options...
55 Fargo Posted November 16, 2011 Author Report Share Posted November 16, 2011 2.2 ohms is not a concern, do you know for certain that the meter you are using is calibrated...probably not..expensive process... There is power to the coil through ballast. I have brought #1 cyl to tdc, as lined up with timing marks on dammper. I have the 1 sprakpulg wire at about 700 oclock in the cap. I have no spark at the points, and this old bugger won't fire up. I am just pouring a bit of gas down the carb to try, but no firing, not sure what to do next. I have had the diz out on bench points look good, the little wire inside looks good, connectiosn all seem nice and ight, I am not sure about this....... Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted November 16, 2011 Report Share Posted November 16, 2011 I must say it is a waste of time to bring number one up to TDC if there is no power to the coil...you are really putting the cart before the horse with this approach...basic trouble shooting would have you get the fire long before trying to ensure it is going to the right tower/plug..you need to back up to your basic troubleshooting and put the scatter gun away... Quote Link to comment Share on other sites More sharing options...
RobertKB Posted November 16, 2011 Report Share Posted November 16, 2011 No spark at points could be many things and I believe that is your problem. Check all wires leading to and from the coil and distributor and maybe change out condensor as you have not mentioned doing this. You need to be sure that the coil is good. If you have power leaving the coil, gotta be something wrong with the distributor. Once you have spark, then worry about the order of the wiring on the distributor as Tim mentioned. Quote Link to comment Share on other sites More sharing options...
Young Ed Posted November 16, 2011 Report Share Posted November 16, 2011 Wouldn't this be the time to take the coil wire out of the dist and put it against the head while someone turns it over? Be careful not to get zapped. Then if you have spark do the same with one of the plug wires and a spark plug. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted November 16, 2011 Report Share Posted November 16, 2011 no need to turn it over..to test the coil is simple..you can ensure you have voltage to the primary input of the coil..secondary wire in the tower and about 1/4 inch from ground to see the spark..now you have two choices..one, if you leave the distributor connected to remove the cap and rotor..turn the engine till the points are open..then simply short across the points gap with a screwdriver a second..when you remove the short..spark jumps from the coil wire..if this does not work ensure the ground.. remember the braided wire here...you may not get a path to ground across the points...you can leave the point gap open, disconnect the wire to the dist. and short the distributor side of the coil to ground for a second and then remove..it should produce a spark..if you have a spoark now..you have a shorted out distributor..check your internal wiring and the pints themselves to ensure they are not grounding out..yes Ihave seen the plastic insulator melt..keep in mind that the points are the connection to the ground and completition of the circuit..closing saturates the coil..opening collaspes the field adn generates the second ignintion voltage Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted November 16, 2011 Report Share Posted November 16, 2011 Fred; Go to the main webpage supporting this forum and read up on static timing. Quote Link to comment Share on other sites More sharing options...
55 Fargo Posted November 16, 2011 Author Report Share Posted November 16, 2011 Fred;Go to the main webpage supporting this forum and read up on static timing. Been there and done it Quote Link to comment Share on other sites More sharing options...
55 Fargo Posted November 16, 2011 Author Report Share Posted November 16, 2011 no need to turn it over..to test the coil is simple..you can ensure you have voltage to the primary input of the coil..secondary wire in the tower and about 1/4 inch from ground to see the spark..now you have two choices..one, if you leave the distributor connected to remove the cap and rotor..turn the engine till the points are open..then simply short across the points gap with a screwdriver a second..when you remove the short..spark jumps from the coil wire..if this does not work ensure the ground.. remember the braided wire here...you may not get a path to ground across the points...you can leave the point gap open, disconnect the wire to the dist. and short the distributor side of the coil to ground for a second and then remove..it should produce a spark..if you have a spoark now..you have a shorted out distributor..check your internal wiring and the pints themselves to ensure they are not grounding out..yes Ihave seen the plastic insulator melt..keep in mind that the points are the connection to the ground and completition of the circuit..closing saturates the coil..opening collaspes the field adn generates the second ignintion voltage Tim, removed cap, and coil high tension wire out of tower, shorted the points, and no spark jumped from end of coil high tension to ground. Not a spark not a short at the points on the screwdriver. Quote Link to comment Share on other sites More sharing options...
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