Do engine armatures have bridge rectifiers in them

Ok I'm just going to explain the whole situation. I have this armature from a weed whacker and I decided to power it with a large coil from an electric motor. It gives off a good arc, about a half inch. But I don't want to make it bigger. I want to increase the arc length with a capacitor. Someone suggested using a Leyden jar. I figured that would work just fine, but it doesn't and I'm not sure why. I thought that maybe it's because the current I'm using might be AC. But I'm pretty sure armatures have rectifiers in them. Do they, and if they do, do you have any idea why my setup isn't working?

Engines don't use electricity to function.

"Devices converting heat energy into motion are referred to as engines, which come in many types. A common type is a heat engine such as an internal combustion engine which typically burns a fuel with air and uses the hot gases for generating power. External combustion engines such as steam engines use heat to generate motion via a separate working fluid."

http://en.wikipedia.org/wiki/Engine