Kevin76 Posted May 21, 2014 Report Share Posted May 21, 2014 (edited) I recently had an entire engine re-build at a shop and have spent the last week re-installing the engine into the car. When I tried to start it, it would turn over but not start. I pulled a spark plug and no spark arced to ground. I have 12 volts going into the coil at the wire lead into the + side, but on the coil terminal it goes to 9V. On the negative side, with the terminal lead to the distributor off, I read 9V at the tab. As soon as I put the wire end on the tab, the voltage goes to zero. The positive side has also has a lead to what looks like a ballast resistor, which I grounded to the block. The points, condenser & rotor in the distributor are new, and I carefully gapped the points. I have read about bad-out-of-the-box rotors, so can change that out; I kept the old one that worked. I live in south east Michigan, USA. Any help would be greatly appreciated. Thanks, Kevin Edited May 21, 2014 by Kevin76 Quote Link to post Share on other sites
peejay4A Posted May 21, 2014 Report Share Posted May 21, 2014 The ballast resistor shouldn't be earthed/grounded. It should be fed with 12v from the ignition switch. There should also be a connection from the starter solenoid to provide full 12v to the coil + terminal whilst cranking. Can you check that your points aren't permanently grounded, it's easy to get the connections on the contacts plate wrong.. With an ohmmeter you should be able to register them opening and closing. Quote Link to post Share on other sites
Steves_TR6 Posted May 21, 2014 Report Share Posted May 21, 2014 As peejay says the ballast resistor should feed the coil with circa 8 volts, which is upped to the full 12 volts when cranking. To get you started I recommend doing away with the ballast resistor just for now. So the coil + goes to ign positive. Coil - goes to the distrib, so that as the point open and close the coil is turned on and off, which is how it works! Try a basic setup to get the car running, then reinstate the ballast once you have it Woking. Hth Steve Quote Link to post Share on other sites
oldtuckunder Posted May 21, 2014 Report Share Posted May 21, 2014 (edited) If you still have no spark at the plug when you have checked all the above and are sure that points aren't permanently grounded, also check the condensor, and replace if you have a spare. Then take one of the plug leads and a plug and connect direct into the coil, and crank and see if you have a spark. If you do then the problem is in the Dizzy, if you don't then re-check all the above, and then find a spare coil to test with. Edited May 21, 2014 by oldtuckunder Quote Link to post Share on other sites
Peter Cobbold Posted May 21, 2014 Report Share Posted May 21, 2014 Very easy to assemble the points so the volts short to earth. Result- no sparks The two circular connectors should be insulated from the threaded post, rather like this: http://www.paulhunt73.webspace.virginmedia.com/mgb-stuff/images/p25conn.jpg And yes we've all done it, once. Peter Quote Link to post Share on other sites
Kevin76 Posted May 21, 2014 Author Report Share Posted May 21, 2014 Thanks for your suggestions, this will give me a direction to go on tomorrow. I'll post back with the results. I greatly appreciate your advice. Kevin Quote Link to post Share on other sites
Kevin76 Posted May 23, 2014 Author Report Share Posted May 23, 2014 Thanks, Peter. I re-assembled the points per your drawing and it fired up. Spent yesterday breaking in the new cam. Good to be on the road again. Thanks to all for your responses. Kevin Quote Link to post Share on other sites
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