My Oliver suffers from a weak spark even after I replaced the plugs, plug wires, points, condenser, cap and rotor, and the coil. I'm wondering if I could simply slap on an external 12 volt coil for a stronger spark.
Explain this to me, Doesn't your Hg have a mag? A 12 volt coil is designed to be used with a distributor and the difference between a 12 volt and a 6 volt coil is that the 12 volt has a rsistor inside the coil to cut it down to 6 volt. Do you have a good blue spark at the points What point gap are you setting the points at and do you have a mag or a distributor?
My Oliver has an International Harvester magneto, or maybe it's a distributor. I don't know how to tell the difference, but would like to. I've played with many automotive distributors, but never any magnetos.
Adam, our OC3 also had an IHC type H-4 magneto when we got it, and it too suffered from a poor spark. I asked the good folks at Standard Ignition and Magneto in Chicago about the correct mag and they said a Wico 1113 or 1337 would be perfect. They said the H-4 mag has the wrong advance for our engine.
I bought a new Wico for $275 and it sparks like crazy, starting very easily and running great now. They threw in a set of solid wires and the push-on ends for free, too!!