Jim Yergin Posted January 10, 2007 Report Share Posted January 10, 2007 Still working on getting my '41 Plymouth started. I replaced the battery and that appears to have solved the cranking problem. Now I believe I may have a coil problem. Last night when I went to check the static timing per the service manual (test light connected to battery terminal on regulator and to the primary wire terminal on the distributor) the light remained on whether the points were open or closed. I disconnected the primary wire from the coil and the test light would go out when the points were open. I then used a continuity tester on the coil terminal for the primary wire to the distributor. The tester showed continuity between that terminal and any ground in the car as well as continuity with the casing of the coil. Should that be or is there an internal short in the coil? Jim Yergin Quote Link to comment Share on other sites More sharing options...
Tim Frank Posted January 10, 2007 Report Share Posted January 10, 2007 Jim, If you have a positive ground system.... As a double check, I would disconnect the primary wires at the coil. . Connect your test light between the the coil + terminal and the wire end that was connected to the coil + terminal. Then run a jumper wire from the negative battery terminal to the negative terminal on the coil. If the results are the same, you can try the service manual coil test if you have an ammeter and a voltmeter. Depending on what you are using to test continuity, you may not be establishing zero ohm resistance i.e. a short. With the primary wires off the coil, if you still have continuity between either of the coil primary terminals and ground, it would be my understanding that the coil would be u/s. Rgds, Tim Quote Link to comment Share on other sites More sharing options...
Jim Yergin Posted January 11, 2007 Author Report Share Posted January 11, 2007 Tim, Thank you very much for your suggestions. It turns out the short is not in the coil but rather in the primary wire from the ignition switch to the coil. The '41's have a through the firewall coil with the primary wire from the ignition switch passing through an armored sheathing to the back of the coil under the dash. To perform the tests you suggested I had to remove the cap on the back of the coil to access the primary wire. That is when I discovered that the insulation on the old primary wire was gone and it was shorting out on the metal cap. That is the one wire I did not replace in my rebuild but it will be replaced now. Your advice led me to the problem and I am grateful for your help. Now I just have to figure out how to remove the ignition switch from the dash to replace the wire. Jim Yergin Quote Link to comment Share on other sites More sharing options...
BobT-47P15 Posted January 11, 2007 Report Share Posted January 11, 2007 Jim....not sure about your model of car, but in a 46-8 Plym, there is a small screw or bolt coming up thru the bottom of the dash to hold that ign switch in place. Otherwise, it slides out from the back. Quote Link to comment Share on other sites More sharing options...
Jim Yergin Posted January 11, 2007 Author Report Share Posted January 11, 2007 Thanks Bob. I plan on taking a look at it tonight. I know it comes out because I installed it years ago but no longer remember the details. Jim Yergin Quote Link to comment Share on other sites More sharing options...
Tim Frank Posted January 11, 2007 Report Share Posted January 11, 2007 Great news, Jim. Having replaced a few electrical components over the years that were still OK, I now assume that the component is fine until I have completely exhausted all other options. I take all wiring off if possible and do some tests from that point. That quickly rules out a problem with the attached wires. Why it took me so long to reach that fairly obvious approach to troubleshooting I have no idea.... Quote Link to comment Share on other sites More sharing options...
Jim Yergin Posted January 12, 2007 Author Report Share Posted January 12, 2007 Bob, You were right on the money. Found the hole in the bottom lip of the dash under the ignition switch, put a screw driver up through the hole and took out the screw holding the switch in place. Switch slid right out from behind and, after disconnecting the wires, came easily out of the car. Once again this forum and its knowledgable participants come through as an invaluable resource. Thanks again. Jim Yergin Quote Link to comment Share on other sites More sharing options...
Young Ed Posted January 12, 2007 Report Share Posted January 12, 2007 Jim You can kind of uncrimp and then unscrew that armored cable piece off the back of the ignition. Dad and I did that to my truck one and were able to get the new wire into the old armor piece. Quote Link to comment Share on other sites More sharing options...
Jim Yergin Posted January 12, 2007 Author Report Share Posted January 12, 2007 Ed, That's good to know. What do you uncrimp? Is it where the armor sheathing goes into the back of the switch or is it the whole back plate? Thanks. Jim Yergin Quote Link to comment Share on other sites More sharing options...
Young Ed Posted January 12, 2007 Report Share Posted January 12, 2007 Where the sheathing goes into the switch. I cant recall if that gave access to replace the whole wire or if there is a joint inside the sheathing now. Quote Link to comment Share on other sites More sharing options...
Rodney Bullock Posted January 13, 2007 Report Share Posted January 13, 2007 JIm, I had a bad experince with the ignition wire on my 1940 where the cable was bent a certain why and it would catch fire or rather get red hot to the touch because of the wire inside touching the metal case. Then when the guy at the shop twisted the ignition switch to the point it broke I thought I was up the creek. Then I remembered a gentleman I met at Carlise some years ago, he had all these ignition coil and ignition cables.If you have yours out of the car just measure it and give this guy a call, he will test it and send you one, mine is old stock and works fine. He is very nice and he is reasonable. Ed Spiegel call him in the evening 724-733-1818 e-mail parts4u@aol.com I would call him. This spring when you go to Carlise look him up he has hard to find stuff for our cars, I tried to uncrump that part on mine once and well I use it to hang stuff on now:rolleyes: win some lose some good luck JIM! Quote Link to comment Share on other sites More sharing options...
Jim Yergin Posted January 13, 2007 Author Report Share Posted January 13, 2007 Rodney, You mean it is not normal to have smoke coming up out of the dash when you turn on the key? Thanks for the tip. I have dealt with that vendor before but I did not know he had the ignition cables. Fortunately, thanks to Ed's information, I was able to detach the armored cable from the switch to replace the primary wire so I don't think I will need to find a replacement armored cable set. What a great resource this forum is. I post a message asking about a problem I am having and within a day Tim provides directions that allow me to pinpoint the cause of the problem. Then I ask how to remove the defective part and again within a day Bob tells me how to do it. Then Ed provides directions on how to disassemble the part and finally Rodney tells me where I can find a replacement if my part can't be fixed. Who could ask for anything more. Thank you all very much. Jim Yergin Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted January 15, 2007 Report Share Posted January 15, 2007 Rodney,You mean it is not normal to have smoke coming up out of the dash when you turn on the key? Thanks for the tip. I have dealt with that vendor before but I did not know he had the ignition cables. Fortunately, thanks to Ed's information, I was able to detach the armored cable from the switch to replace the primary wire so I don't think I will need to find a replacement armored cable set. What a great resource this forum is. I post a message asking about a problem I am having and within a day Tim provides directions that allow me to pinpoint the cause of the problem. Then I ask how to remove the defective part and again within a day Bob tells me how to do it. Then Ed provides directions on how to disassemble the part and finally Rodney tells me where I can find a replacement if my part can't be fixed. Who could ask for anything more. Thank you all very much. Jim Yergin So Jim; Are you up and running? Quote Link to comment Share on other sites More sharing options...
Jim Yergin Posted January 15, 2007 Author Report Share Posted January 15, 2007 Don, Not yet. I still have to reinstall the repaired ignition switch. Hopefully that will happen today. Jim Yergin Quote Link to comment Share on other sites More sharing options...
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