Electric Choke Draining Battery?

Discussion in 'Classic Mustang Specific Tech' started by pyroman, Feb 8, 2010.


  1. pyroman

    pyroman Founding Member

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    Has anyone had this problem? Something was draining my battery so what I did was wired a tail light bulb in series with the battery to see if it would light up. It did, so I started pulling fuses. (Saw this tip on here from somebody). Second fuse I pulled was for the electric choke and the light went off. Holley says to hook the choke up to a constant 12V. The choke will draw current when the car is off right? How much should it draw? Enough to light up the tail light bulb? (Is that 3A?)

    The only wire I ran was the constant 12V. To make sure it wasn't grounding out I removed it and just ran a wire straight from the choke to the starter solenoid post. Light was still on.

    So does this sound like a issue with the choke or just a weak battery?

    Thanks
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  2. Velox

    Velox New Member

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    The electric choke should NOT have constant 12V, of course it will drain the battery if it is powered continuously. The choke should ONLY have 12V when the ignition is on. The only way the choke will work is to have power off to it when the car is off, i.e. 'cold' then when key is on, choke receives power, warms the element in the housing and pulls off the choke butterfly as the engine is running. To have 12V always on the choke not only drains the battery down, but defeats the entire purpose of having an electric choke IMHO. Recheck the Holley instructions, I'm sure they indicated the choke should be wired to a key-on 12V source :) Here is a quote from the Holley PDF file for installation of one of their electric choke kits: "Connect the other end of the wire to a fused ignition activated 12V source. The choke cap should only get voltage when the engine is running."
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  3. pyroman

    pyroman Founding Member

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    Ah good call, I suppose I just misread the instructions. Thanks :nice:

    Yep, just went back and read the instructions. Don't know how I missed that one it was clear as day. Man I feel like dolt, haha.
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  4. JonK

    JonK Member

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    I ran mine to the stator STA post on back of the alt., this is the way ford did it later. Only has juice when in the run position. Didn't have to run a wire through the firewall or install a fuse like this.
    Jon
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  5. Wart

    Wart I'm Mad as HELL and I'M not Gonna Take it ANYMORE! Founding Member

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    Been a while since I looked at the schematic for a 'classic' alternator.

    Ford did wire the electric chokes to a post on the alternator, I believe the post was marked Stator, that post was wired into either one leg of the stator OR was wired so it would get only 1/2 wave rectification so the wire wasn't actually getting 12 volts AND there was one heck of an AC component to the supplied power voltage.

    Trivia: A friend hooked a small relay up to the electric choke circuit to power something when the engine was actually running. The relay buzzed.
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  6. pyroman

    pyroman Founding Member

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    Stupid question coming...

    I rewired the choke to switched power so that is not longer a problem. However, during my investigation I took off the choke cap and "unwound" the spring. The carb is Holley 5170 I believe. Well ever since I did that I haven't had a properly working choke and am having driveability issues. My question is, once I put the cap on, do I have to preload the spring by rotating it clockwise or counterclockwise 'x' amount of times?
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  7. pyroman

    pyroman Founding Member

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    Anyone? Or would I be better off calling holley?
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  8. 2+2GT

    2+2GT Well-Known Member

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    No rotating. It needs to be properly connected between the choke and cap. The spring/cap should be set so the the choke is applied with the power off. Connect the choke properly, and run the engine. Within a few minutes the choke should be fully open.
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  9. Wart

    Wart I'm Mad as HELL and I'M not Gonna Take it ANYMORE! Founding Member

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    Not familiar with that exact choke,

    In general, with a cold engine, you reinstall the choke cap and "spring" making sure all the tabs and slots and such are properly engaged.

    Then you turn the cap the correct direction till the choke closes.

    Thats just a base setting.

    The further the cap is turned past this point the longer it takes for the choke to open.

    Something that can cause drivability problems is a malfunctioning choke pull off.

    Another thing is carb heat. Carb ice is a ****.
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