I am a new owner of a 25 model t 4 door. It runs perfect. Yesterday I decided to change the oil in this car. After I drained the old oil out I filled the engine with the new oil I added about a pint more than needed. When finished I started the engine to let it warm up and drive. The engine ran great on coils but when I switched to mag the engine quit. I drained the excess oil out and the engine ran fine. any reason why the small amount of excess oil made this happen.
You may have an intermittent problem with your ignition switch,but oil didn't have anything to do with it.
Jack: Thanks for helping a " Newby" .... Goodf advise
Wayne, assuming you did not use some sort of graphite oil, a tad of "over fill" of any kind of petroleum base oil should have no influence as to yes or no as far as the mag is concerned. Check the mag voltage at the mag post and then go from there.
If the output from the MAG is intermittent, I'd check the switch, as Jack says, and also the mag post connection.
By the way, welcome to the affliction. Here are a couple of links for all new T owners.
http://dauntlessgeezer.com/DG80.html
http://dauntlessgeezer.com/DG79.html
Check the mag contact post too. (Remove and clean) Dumping new oil into the filler can wash old junk into flywheel portion the pan.