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BW overdrive troubleshooting

Discussion in 'The Hokey Ass Message Board' started by cb186, Jul 30, 2013.

  1. cb186
    Joined: Jul 5, 2013
    Posts: 264

    cb186
    Member

    Ok, so I finally got my overdrive all hooked up and working, except there is a problem that I haven't been able to figure out. Whether the OD is in or locked out, once the governor closes(above the 28mph range), it seems that the ignition is cutting out at any more than a cruising throttle position. I can run it hard thru 1st, shift into second and when the governor kicks in, WHAM, it almost bounces you off the steering wheel. You can roll off and cruise just fine in lock out or let it shift into OD, and it does the same if you squeeze on it. I first noticed it when I initially test drove the OD for the first time and kicked it down, it "stalled" for as long as I held it to the floor.
    Troubleshooting brought me to find that if I disconnected the governor wire(via the kickdown switch) at the relay, it ran just fine(of course OD didn't work then).
    It's almost like the coil is getting shorted out through the relay. I swapped out the relay for another and it does the same thing. I wired it per this schematic, including having wired the black wire that feeds the Ignition terminal on the relay, directly to the battery terminal on the coil, instead of off the key switch(for ease of wire routing), as some schematics I've seen show. I cant think of any reason that this should make a difference, as it's doing the same thing, just a different connection spot.

    Anybody ever seen this or have any thoughts? Maybe I'm missing something so obvious that I'm looking right past it. My next step is to see if a diode with keep what I perceive as a voltage back feeding issue, to the wiring(ign feed).

    [​IMG]
     
  2. PackardV8
    Joined: Jun 7, 2007
    Posts: 890

    PackardV8
    Member

    You've diagnosed your own problem. You've just got to find out why the governor is grounding to ign. Check the kickdown switch. For some reason, there are two different kickdown switch internal wirings. Use a VOM on all four terminals to determine what is normally on and normally off.

    jack vines
     
  3. J Twitero
    Joined: Apr 15, 2011
    Posts: 105

    J Twitero
    Member
    from Minnesota

    The orange wire from the solenoid to the kickdown switch and back to the ignition coil is probably the circuit giving you trouble. My understanding is it is supposed to ground the ignition when you kick down to allow the OD to downshift when you want "passing gear". I believe that circuit is closed in the solenoid when OD is engaged, and it should open as soon as OD is disengaged.

    Sounds like PackardV8 is on the right track with the kickdown switch, the circuit should be open on that side of the kickdown switch until you floor it. Then it should open the power circuit for the solenoid, allowing it to disengage, and close the circuit to the points, allowing the motor to temporarily cut power (until the OD solenoid moves) so it can shift.

    On my 52 Ford, I did not originally have OD, so I just installed a toggle switch to power the solenoid. I also bypassed the governor and the points cut out, so I can have OD at any speed in any gear, but I have to pedal the motor to shift both ways. That may be an option for you if you don't mind it not being original.
     
  4. Is it a 6 volt or a 12 volt system?

    And does it have the correct matching soloinoid for that voltage?

    Oldmics
     

  5. cb186
    Joined: Jul 5, 2013
    Posts: 264

    cb186
    Member

    I did check the status of the kick down switch(initially had it backwards, as laying under the car had my brain see the switch upside down to the diagram). The switch needs to be normally closed so that when the governor closes, it complete the grounding circuit through the kick down switch and grounds the coil of the relay, allowing it to pull it, thusly sending power(still hard to keep my brain straight with the positive ground thing) to the solenoid. If the governor circuit ran through the normally open side of the switch, it would only pull in the solenoid while at full throttle. At least that's how I'm seeing it.

    Where it seems like my back feeding issue is, is if you measure the voltage at the Ign terminal or the TH SW terminal, it reads ~3v either way, rather that 6v(current draw from the coil). I have ordered a couple of 6v Bosch style relays to try out, as I was thinking with the diode across the coil might help, but testing my theory on a 12v coil doesn't support my idea.

    And yeah, I prefer to keep it working in the stock manner, as opposed to adding switches. To be honest, I wish the OD worked is a different fashion than it does.
     
  6. Your not acquiring your 6 volts from the low side of the ballest resistor - are you?

    That solinoid will do exactly as you describe your problem when it does not have full voltage.

    Oldmics
     
  7. cb186
    Joined: Jul 5, 2013
    Posts: 264

    cb186
    Member

    I don't think so, but to be honest, I'm not sure. I tapped off of the coil at both the "coil" terminal(power coming from the ignition switch) and the other is on the distributor pole, which also has one wire running to the distributor, just like the schematic shows.

    Oh, and yes, it is a 6v system. Now that I think about it, I need to double check on the solenoid. My dad pieced all the parts together 25 years ago, and the tranny itself is out of a 55 ford, but I believe that the solenoid was separate and that it's 6v. I will double check that, just in case.
     
  8. zibo
    Joined: Mar 17, 2002
    Posts: 2,346

    zibo
    Member
    from dago ca

    Not to say that the original system isn't good or anything,
    but it's easy to just ditch all the extra except for the relay to the solenoid,
    and run a toggle/headlight switch from the relay to the dash somewhere.
    So no governor, coil or kickdown wiring.
    Its simple to drive and hassle free.
    TP
     
  9. cb186
    Joined: Jul 5, 2013
    Posts: 264

    cb186
    Member

    I have confirmed that it is a 6v solenoid, so everything checks out as far as I can tell. I think I will disconnect the wire coming from the kick down switch that goes to the distributor(this should prevent the kick down feature but allow it to go into OD, as far as I can tell) and also move the wire on the Bat terminal on the coil directly to the battery, just as a test.
     
  10. PackardV8
    Joined: Jun 7, 2007
    Posts: 890

    PackardV8
    Member

    Yes, never, ever wire anything else off of the hot side of the coil. Can't tell you how many problems I've seen caused by that bad science move.

    jack vines<!-- / message -->
     
  11. cb186
    Joined: Jul 5, 2013
    Posts: 264

    cb186
    Member

    Yup, that took care of it. Rewired it directly to the battery and then test drove it. No issues at all. Now I'm redoing my harness to connect it to the ignition switch.
     
  12. Mike51Merc
    Joined: Dec 5, 2008
    Posts: 3,855

    Mike51Merc
    Member

    These 6V solenoids are very sensitive to voltage drops. Anything less than 6V and they hang in limbo between engaged and disengaged, causing the throw coil to be energized and drawing a lot of current, thereby making the problem even worse.

    That being said, anyone who has one of these should also be aware that there is a fiber insulator disc inside the solenoid can. This insulator can disintegrate when exposed to oil, causing the kickdown contacts to be permanently engaged. In other words, flooring the throttle kills the engine for as long as the throttle is held down.
     

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