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Technical Help Flat head only runs while key is turned

Discussion in 'The Hokey Ass Message Board' started by Youngster51, Apr 16, 2019.

  1. Youngster51
    Joined: Dec 10, 2014
    Posts: 72

    Youngster51
    Member
    from Fresno ca.

    I just picked up a 53 Ford Victoria with a older rebuilt flathead that hasn’t ran in a few years. I tried starting the Flathead and it would only run while the key is turned and cranking I can rev the Flathead using the key also which is wild. So far I have replaced the plugs, plug wires, coil, ballast resistor, key switch, new battery, rebuilt carb. It is getting fuel checked spark from coil and spark from cap to plug all have great spark. The Flathead has been hopped up and is running a Mallory unilite distributer. I can not figure out why as soon as I let off the key it dies please help
     
    Last edited: Apr 16, 2019
  2. TrailerTrashToo
    Joined: Jun 20, 2018
    Posts: 268

    TrailerTrashToo
    Member

    Symptom indicates no voltage on the coil when the Key is in the "ON" position. Break out your voltmeter (or test light). Check the voltage at the ignition coil with the key in the "ON" position. I suspect that the wires to the ignition switch are in the wrong places.
     
  3. m.kozlowski
    Joined: Nov 2, 2011
    Posts: 117

    m.kozlowski
    Member

    Or ignition switch is broken.
     
    clem likes this.
  4. Kiwi 4d
    Joined: Sep 16, 2006
    Posts: 2,376

    Kiwi 4d
    ALLIANCE MEMBER

    So the starter is spinning and the engine is running let the key go back to power from the start position and it dies, correct?
    If this sure seems like a bad ballast ,though you have checked this , is it worth trying another ballast?
     
    Saxman likes this.
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  5. Petejoe
    Joined: Nov 27, 2002
    Posts: 9,807

    Petejoe
    ALLIANCE MEMBER
    from Zoar, Ohio

    If that’s the case, it seems odd your starter hasn’t burnt up. Even Being engaged at a low idle would be the end of that starter. Please let us know what you end up finding?
     
    egads likes this.
  6. GTS225
    Joined: Jul 2, 2006
    Posts: 1,062

    GTS225
    Member

    Youngster; In the "start" position, the ignition switch bypasses the ballast resistor, but in "run", power goes through the resistor to the coil.
    Trailer Trash's suggestion is a good one, as you say you've replaced the resistor. Check that out, and if it doesn't help, look into the voltage requirements for that Unilite. The ballast resistor drops the voltage down to give longer life to the points and coil. Might it be to low for the Unilite to operate?

    Roger
     
    Atwater Mike, ClayMart and Saxman like this.
  7. sunbeam
    Joined: Oct 22, 2010
    Posts: 3,910

    sunbeam
    Member

    You are only getting power from the resister bypass terminal on the starter solenoid.
     
    Atwater Mike likes this.
  8. 32phil
    Joined: Nov 24, 2007
    Posts: 44

    32phil
    Member
    from New York

    The first thing I would do.....
    If it has a conventional Ford solenoid I would check to see if the main feed for the whole car is on the wrong side of the solenoid. You're looking for a larger wire about 10 ga. with a large loop connector big enough to mount on the solenoid. It's probably on the solenoid where the battery cable from the solenoid to starter cable attach. Move it to the other side of the solenoid where the battery cable FROM the battery is.
    When you turn the key you energize the solenoid/starter and the car will start and run....it stops running when you let the key go because it's dropping the main power feed when the starter drops out.
    I think......
     
    alanp561 likes this.
  9. Youngster51
    Joined: Dec 10, 2014
    Posts: 72

    Youngster51
    Member
    from Fresno ca.

    I put a test light on the positive side of coil while key is on and no power. the hot wire coming from the Mallory unilite is not running thru the ballast resistor it is mounted to the positive side of coil. on the ballast resistor there is a wire running to a switch under the dash and a wire running from the switch to positive side of coil
     
  10. Youngster51
    Joined: Dec 10, 2014
    Posts: 72

    Youngster51
    Member
    from Fresno ca.

  11. TrailerTrashToo
    Joined: Jun 20, 2018
    Posts: 268

    TrailerTrashToo
    Member

    1. Most likely, wiring error at the ignition switch.

    2. Or defective ignition switch.

    With the test light, start at the ignition switch a verify the switch positions, i.e. OFF, ACCESSORY, RUN and START.
     
  12. Mr48chev
    Joined: Dec 28, 2007
    Posts: 24,547

    Mr48chev
    ALLIANCE MEMBER

    SWITCH UNDER THE DASH! did you turn that switch on or see if there is power to it? My guess is that someone put it in the line either as the primary ignition switch after the ignition switch went bad or as an anti theft device or otherwise disable the ignition. Check to see if you have power to that switch with the key on (or off for that matter and then power coming out of it.
     
    X-cpe and TrailerTrashToo like this.
  13. AChopped1950ford
    Joined: Sep 5, 2018
    Posts: 84

    AChopped1950ford
    Member

    With the mallory unilite distributor you do not use a ballast resistor, I believe your wiring is not correct, simple repair though.
     
  14. How the fuck do you rev the engine with the key?!? WTF is going on.
    Google Mallory unilite wiring

    No power out of ignition switch in run position ???
    Or
    No power to coil in run position ??
     
    Petejoe likes this.
  15. BJR
    Joined: Mar 11, 2005
    Posts: 5,388

    BJR
    Member

    When you find out what the problem was, please let us know and thank whoever gave the correct solution.
     
  16. sunbeam
    Joined: Oct 22, 2010
    Posts: 3,910

    sunbeam
    Member

  17. Youngster51
    Joined: Dec 10, 2014
    Posts: 72

    Youngster51
    Member
    from Fresno ca.

    I squeezed under the dash and started following wires from the ignition switch and ballast resistor the switch was good found that the switch was wired into the headlight switch and the electric fan switch so to start the engine you have to have the headlights on fan on and the switch to the ballast resistor on... kill switches was the problem thanks for all the responses
     
    AChopped1950ford and alanp561 like this.
  18. I think it's like when your car won't start and you instinctively turn the key harder, hoping that by doing so it will make it start. :mad: Except it usually doesn't. And you end up twisting the key off in the ignition lock. :oops:
     
  19. See how simple that was :p:D
    They wired it like the green acres tractor
    Bet the dome light needs to be on for the blinkers to work,,, at least the door opened
     
    Last edited: Apr 18, 2019
    AChopped1950ford likes this.
  20. Atwater Mike
    Joined: May 31, 2002
    Posts: 9,220

    Atwater Mike
    ALLIANCE MEMBER

    Yeah! ,,,At the Junctionnn.......
     
    31Vicky with a hemi likes this.
  21. blowby
    Joined: Dec 27, 2012
    Posts: 5,725

    blowby
    Member
    from Nicasio Ca

  22. AChopped1950ford
    Joined: Sep 5, 2018
    Posts: 84

    AChopped1950ford
    Member

    Glad you got it figured out.
     

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