choke issue
Elder User
Joined: Sep 2003
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The Ford electric choke connected to a special winding coming off the alternator. My experience has been that connecting these to 12 V will burn them out.
I've seen the choke voltage reported as anything from 5 to 8 V.
Electric chokes are available for 12 V. My Bobcat has one that came off a Holley carb. The housing is metal. You could look around and try to find one.
Be sure to connect the choke to the alternator, so that it only heats when the engine is turning. Mine is connected to the ignition switch, and it will drain the battery fast if the key is left on.
I've seen the choke voltage reported as anything from 5 to 8 V.
Electric chokes are available for 12 V. My Bobcat has one that came off a Holley carb. The housing is metal. You could look around and try to find one.
Be sure to connect the choke to the alternator, so that it only heats when the engine is turning. Mine is connected to the ignition switch, and it will drain the battery fast if the key is left on.
Posting Guru
Joined: Dec 2002
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From: chicago burbs
doesn't make sense to me? any voltage at the ALT is going to be 12v or higher if the engine is running. all vehicles i've had w/elec choke had a wire in the engine wiring harness. Wizard, what year model is your 70 C in? and what was the original engine/choke?
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New User
Joined: Mar 2004
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The engine came out of a 71 couger, at least that is as close anyone can come to it. I got the truck w/the 351c in it and the choke was not hooked up. Also the original wiring harness was so messed up by whoever installed the engine ( found out that a wrecking yard installed it according to the previous owner who died about 5 yrs ago) that it is hard to tell what wire went were. Does anyone know where I can get my hands on a wiring schematic for a 70 F-100?
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From: chicago burbs
i remember it being a black wire with a female bullet connector on it, and a short jumper with a male bullet to a female spade that connects onto the choke terminal. maybe go junkin just to look at some unmolested wiring harnesses, you might even find one you can use?
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From: (near) Denver USA
OEM electric chokes are powered by the stator terminal on the alternator, which taps into the +V output from one power diode (of the pair) on each stator winding.
Since the stator terminal gets only half of the alternator's output, nominal voltage at the stator is +6VDC.
Actual voltage at the stator is half of the alternator's DC output, which usually exceeds 12VDC.
Since the stator terminal gets only half of the alternator's output, nominal voltage at the stator is +6VDC.
Actual voltage at the stator is half of the alternator's DC output, which usually exceeds 12VDC.
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"Since the stator terminal gets only half of the alternator's output, nominal voltage at the stator is +6VDC."
Exactly.
Another way to do it would be to find an old ballast resistor and wire the choke through it. I remember the Mopars had ceramic ones that mounted on the firewall.
Exactly.
Another way to do it would be to find an old ballast resistor and wire the choke through it. I remember the Mopars had ceramic ones that mounted on the firewall.