willie Posted June 4, 2017 Share Posted June 4, 2017 Hello everyone!!! I am having trouble starting one of my parts cars. I don't have spark to the plugs so I backed up to the coil. No spark from the coil to the dist. I check the pos and neg side of the coil and no juice. So I changed the coil as I am removing the coil I noticed the condenser wire is broken. I am not sure if the points cond is the same but that's all I have so I put one on and a used coil in, and now I have juice on the pos and neg when I turn the key on, but still no spark to the dist when I crank the car. 1st question Will any GM coil work as long as its an 8 cyl, how do I know they are good? 2nd will the points cond work on the outside of the dist? Thanks for the help guys Quote Link to comment Share on other sites More sharing options...
cny first gen 71 Posted June 6, 2017 Share Posted June 6, 2017 I think any 8 cyl coil will work but I think thats a noise supressor not a condencer but not 100% positive. Hopefully someone else wll chime in. Quote Link to comment Share on other sites More sharing options...
willie Posted June 18, 2017 Author Share Posted June 18, 2017 Thanks Steve I am going to change out points, cond and the noise suppressor. Before I change the coil again. Quote Link to comment Share on other sites More sharing options...
Toppless72 Posted July 1, 2017 Share Posted July 1, 2017 Willie, In order for the coil to work you must deliver power to the positive side. In your first post you mention that you checked it and there was no power at either side. That is the first problem to solve. When you checked it was the key in the run position? If not turn the key to the run position and using a VOM or DVOM see if there is power and how much. The minimum would have to be 9 volts for the car to even try to start. If you want to test your coil before you change it here is a simple method explained. https://www.yourmechanic.com/article/how-to-test-a-spark-plug-ignition-coil-by-eduardo-ruelas Quote Link to comment Share on other sites More sharing options...
willie Posted September 4, 2017 Author Share Posted September 4, 2017 Hello everyone, I still can NOT get the car started. I changed everything and the coil again. I changed the coil(again), the points, cond, noise supressor, cap, and rotor. I have the same as before. When i put the key on i have power to the positive and neg side of the coil, but i cant get anything out of the coil going to the dist. The car spins fine just no spark from the coil. Remember this is a parts car, hasnt run for a few years. Could it be something with the neutral safety switch, as i have to pull the shifter from park to neutral for the car to spin? Thanks for all the help i can sure use it now? . Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted September 4, 2017 Share Posted September 4, 2017 Is the rotor spinning? Quote Link to comment Share on other sites More sharing options...
willie Posted September 4, 2017 Author Share Posted September 4, 2017 Hey Rod, Yes it is. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted September 4, 2017 Share Posted September 4, 2017 If you have voltage to the positive side (where it's getting its voltage from can be important, but let's look at why the coil is not firing) you should be able to trigger the coil with the distributor cap off manually by having the power on and slightly moving the rotor back and forth, where the points are just barely closed and opened. The points make or break the contact.. so if you have a grounded primary circuit it will not discharge the coil. You should be able to see the points arc or spark if the primary side is working fine, the secondary side of the coils ouput via the rotor and cap, distribute the high voltage to each cylinder. Make sense? I guess I should have asked if the plugs are firing but I'm assuming you have already checked that? Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted September 4, 2017 Share Posted September 4, 2017 Willie, I'm assuming this ignition system is stock and separate points and condenser, also no wobble in the distributor shaft, cause that right there will have a huge affect on the system. At times unplugging the vacuum advance will let you get started when you have a wobbly distributor shaft. Let's see what you find. Quote Link to comment Share on other sites More sharing options...
willie Posted September 4, 2017 Author Share Posted September 4, 2017 Hey Rod yes it is a stock ign. I have checked the plugs for spark the first time, no spark so i started working backwards to the dist, no spark, then the coil, no spark. so i checked the positive and neg leads and i DID have power. i also checked as you suggested check the points for spark. as i didnt see at any time spark from the points i did check the neg side of the coil and traced it back into the dist and connected to the points and there was power there. So i assumed there was power going thru the actual points. When i purchased the car i know it ran, so something happened between then and now. (a few years now). Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted September 4, 2017 Share Posted September 4, 2017 Willie, Electrical is tricky and at times it can work intermittently, but not that difficult to troubleshoot. I would stay on the basics first, using a light continuity tester can be beneficial. Assuming the points are correctly gapped (dwell angle) set the cam on the distributor on it's highest peak, are the points open? If not gap them (.018 - .019 in) with a feeler gauge. That should get you close enough to see spark in the points, assuming again points aren't pitted, if no spark, you have either a bad condenser or your system maybe grounded on the negative side from the coil to the distributor. You have to establish a point arc to move on.. otherwise you're throwing guesses at it. Let's see what happens? Quote Link to comment Share on other sites More sharing options...
willie Posted September 4, 2017 Author Share Posted September 4, 2017 Rod, thanks for the help. I will check again. If i checked power from the neg side of coil and followed the wire down and into the dist isnt that the wire that connects to the points in the dist? I did and it has power there, so i should have power at the points, but i never looked to see the spark jump. I will do that today. I am also going to check and see if that wire from the coil to the dist is not grounding out somewhere. Quote Link to comment Share on other sites More sharing options...
willie Posted September 4, 2017 Author Share Posted September 4, 2017 Hey Rod, upon further checking I found (like you mentioned) a broken wire that was grounding out. Got it running (not so hot) but running. Now I can get it out of the way. Thank you again Rod, Joe and Steve Quote Link to comment Share on other sites More sharing options...
Rob Peters Posted September 4, 2017 Share Posted September 4, 2017 What a great group here.... Can you drive it to Carlisle next June Willie? How is the one you are restoring coming, will it be done for the 50th anniversary of Monte Carlo in June 1970 in Carlisle? rob Quote Link to comment Share on other sites More sharing options...
willie Posted September 5, 2017 Author Share Posted September 5, 2017 Hey Rob, How are you? This is a parts car, but i need to move it to get the trailer out. As far as the other one goes, its coming along. Just got the motor back from being rebuilt. Now i have to get the tranny done. I am hoping to have it done by the 50th.Anniversary. Would love to have it done so i can bring it up for then. Quote Link to comment Share on other sites More sharing options...
Leghome Posted September 5, 2017 Share Posted September 5, 2017 Rob you better edit your reply to Willie. I don't think June 1970 is coming any to soon Quote Link to comment Share on other sites More sharing options...
willie Posted September 5, 2017 Author Share Posted September 5, 2017 LOL Larry i forgot to mention that to him. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted September 5, 2017 Share Posted September 5, 2017 Good going Willie. Glad to be of help. Though not a fan of standard ignition, I'd say it works crudely and perhaps primitive by today's standards, (no pun intended) though a couple of easy to replace parts in any tool box, would get you back on the road fairly quick. Iffy is the old popping and leaky condenser that will throw many of seasoned mechanics for a loop. Acts similar to a carbon cracked distributor cap, stumble and popping all over the place.☺ Quote Link to comment Share on other sites More sharing options...
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