external resistor

Henryv111111 · May 19, 2011

Many thanks to all who responded to my post. I did not relaize that the points had to be closed to read a voltage drop across the resistor. I recently aquired a Economy tractor they were made in 38 & 39 and sold by Sears Roebuck. They a had a Model A Ford motor.It appers to have been converted to 12V and I was trying to figure out the wiring setup. Oh I do have several IH tractor as well so Iam qualifed to post on this site. Thanks again

John T · May 19, 2011

Congratulations, sounds like you got it now. Yep the voltage drop ACROSS the resistor by ohms law is I x R soooooooooo if I = 0, Voltage drop = 0 and 12 in still 12 out (12 - 0 = 12) even if you had a ton of resistors hangin out there. The distributors points are merely a contact switch when closed allows the coils primary (+ any series ballast) to flow current and then when the high cam lobe opens the points, the current is interrupted which causes the coil to achieve high voltage (on its HV tower) necessary to arc jump current across the plugs gap to ignite the highly explosive compressed fuel air mixture BOOM

Sheesh, the first wife (she who must be obeyed) now says I gotta mow grass before going to the Bluegrass fest

John T

external resistor

Henryv111111

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John T

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