A better 12volt idiot light for your 8n

The problem with the "wedge plug" #194 bulb is finding a suitable socket that you can mount on the instrument panel. Good luck.

A bayonet bulb with similar electrical properties is type #1891 (240mA @ 14v), and Radio Shack makes a nice barrel-style holder for it with a translucent red screw-off cap (part# 272-325); all you need is a 9/16" dia (I think) hole in your dash.

I passed on the diode exciter alternative (diodes can fail). My bulb will fail also, but it's sure easy to replace it when it does.

I'm using my old pulley on the alternator, so after starting I have to rev up to about 1000 rpm briefly to excite it, but then the light goes out and my voltmeter moves from 12v to 14v and off I go.

Once "excited", the alternator continues to charge at all RPM's except idle; with my big pulley it just doesn't spin fast enough at 400 RPM to produce any juice. But it doesn't sit around just idling very much.

Obviously you like your method and not mine, and I like mine and not yours.

It's a free country; you did it your way and I did it mine. So there we are.

I finished my replacement of a poorly done 12-v. conversion in November. I used the diode. Kinda wish I'd opted for the light. Maybe, when the diode finally fails.....

Ron

Brian

That wire is tied to the regulator and once the alternator is excited it will backfeed 12 volts to the ignition. You can put in a blocking diode or a light bulb (factory solution) which prevents the backfeed and also gives you an indication whether the alternator is putting out voltage.

JerryU

Unless your alternator has a big pulley on it like mine, which at idle causes it to spin so slowly it won't put out any current.

So unless you're using the fancy one-wire alternator, you've got to wire in that bulb or diode...