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  • skyway
    replied
    FYI, I’ve had very good luck with some pretty bad looking (even junkyard) kickdown switches working just fine.

    Leave a comment:


  • NCDave51
    replied
    Yes this is the factory kickdown switch - one side of the switch (two of the wires on opposite sides of the block) will break the circuit to the “hold-in” coil of the solenoid and the other pair will simultaneously short the ignition for a split second to give a hiccup in torque, which finally allows the spring-loaded pawl to retract and return to conventional drive.

    It all happens in a second. When you lift the foot up again, you open the ignition ground circuit and re-establish the solenoid hold-in circuit. Because you’ve left the cable in the same position, the system is ready to re-engage.

    In the photo you’ve shown here, all four wires have been cut or removed so that switches not going to do anything. Replacement switches are quite cheap - less than $40 in most places.

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  • jackb
    replied
    that's your kickdown switch. Pretty stout item, but might need cleaning. Find yourself a schematic and you might get lucky in all connections and won't have to worry about 30+ posts to figure it out and you might just save the tranny.....

    Leave a comment:


  • Rafe Hollister
    replied
    Thanks so much, I am understanding this more, and with 400 miles on my Studebaby, I'm getting more familiar. A mechanic friend mentioned that there was a thing under the hood that was disconnected, I've attached a picture, is this the kick down switch? I'll have to try a down shift to 2nd while in OD to see if I can get good passing power, because acceleration at 70mph/2000 rpm is leisurely at best. Also, with my set up, what would happen if I tried to disengage OD at speed, flipped the toggle and pushed the handle in? What if I just flipped the toggle?

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  • NCDave51
    replied
    Originally posted by Ross View Post
    When in reverse the shift rail blocks the overdrive pawl so it can not move in and engage. So even if you did get up to 30 in reverse and the solenoid fired it could not push in the pawl. That is why the lockout switch is not strictly necessary and was later eliminated.

    By the same token, that is why you can not shift into reverse if your unit is wired up so that the overdrive is engaged full time. The shifter rail will hit the side of the pawl and prevent engagement.
    Perfect thanks - I’m not sure I’d like to see any Studebaker go 30 mph in reverse...

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  • Ross
    replied
    When in reverse the shift rail blocks the overdrive pawl so it can not move in and engage. So even if you did get up to 30 in reverse and the solenoid fired it could not push in the pawl. That is why the lockout switch is not strictly necessary and was later eliminated.

    By the same token, that is why you can not shift into reverse if your unit is wired up so that the overdrive is engaged full time. The shifter rail will hit the side of the pawl and prevent engagement.

    Leave a comment:


  • gordr
    replied
    Originally posted by NCDave51 View Post
    Great thread as always. The B-W overdrive was genius when you realize it was a creation of the 1930s-1940s.

    A further comment on the “reverse” situation.

    Folks may recall that there was a rail lockout switch on the R-10 units; when I was restoring my Willys, this was deleted in or around 1952. It was a normally-closed switch that was wired in series with the governor. If the operator selected reverse, the end of the shift selector rail contacted the switch and killed the ground circuit from governor to solenoid.

    My question is when would the governor at speed ever be involved with selecting “R”? Maybe that’s why it was discontinued?
    I think that switch also interrupted the governor circuit when OD was manually locked out, thereby saving a little electrical power.

    Leave a comment:


  • NCDave51
    replied
    Great thread as always. The B-W overdrive was genius when you realize it was a creation of the 1930s-1940s.

    A further comment on the “reverse” situation.

    Folks may recall that there was a rail lockout switch on the R-10 units; when I was restoring my Willys, this was deleted in or around 1952. It was a normally-closed switch that was wired in series with the governor. If the operator selected reverse, the end of the shift selector rail contacted the switch and killed the ground circuit from governor to solenoid.

    My question is when would the governor at speed ever be involved with selecting “R”? Maybe that’s why it was discontinued?

    Leave a comment:


  • Corbinstein0
    replied
    Sounds like your toggle is setup the same way as mine. I did it as a bypass for the entire system mainly due to laziness, and lack of parts for a proper repair.
    When Toggled on for OD, mine won't go into reverse either. Nor will it come out of OD on its own. Makes you think more when driving.
    Had the same thing happen one day when I tried to put it in reverse and finally after a DUH moment, realized that I read that reverse won't work when OD is engaged.
    turned off the toggle and worked fine.

    Now I just need a Dozen "round tuits" to get it fixed properly.

    The good news for you may be that the mechanical part works fine, or most nearly so.

    Remember this, the OD has a plug for checking and filling the Gear Oil separate from the Transmission.
    meaning that it needs to be checked periodically same as the transmission.

    Leave a comment:


  • gordr
    replied
    Originally posted by Rafe Hollister View Post
    Thanks for the advice, especially about reverse. Today I was in OD, stopped the car, tried to put it in reverse but it would not shift. Then I took it out of OD and reverse worked fine. I can keep my car in OD all the time, just did 25 miles today, freeway, stop lights, all gears and neutral, stayed in OD the whole time. Maybe that is what the toggle switch does? I will check tomorrow to see if it comes out of OD on its own. My car is in really rough shape, busted windows, won't roll up, guage lights out, nor drivers door lock, no back seat, so perhaps my OD question was a bit premature on my priority list.
    But on the good side, my cars has good brakes, hd front sway bar and rear too, R3 exhaust manifold, dual exhaust, edelbrock, etc... it is deffinitely a hot rod Hawk.
    Rafe, evidently somebody has wired the overdrive to be completely manual. That was an old hot-rodders' trick. Borg-Warner spent a lot of time and trouble designing an Automatic Overdrive just to preclude a situation like you have just described. They even named it "Automatic Overdrive". The T-handle on your dash is used to enable or disable the overdrive mechanism, which is really a 2-speed automatic transmission hung on the back of a regular 3-speed manual transmission. Pull out the T-handle, and the overdrive unit is locked OUT, and the car drives exactly as it would with a straight 3-speed. Push the handle in, and overdrive is enabled, and automatic shifts occur as programmed by the governor and the accelerator pedal. With overdrive enabled, torque flow goes through an over-running clutch (aka sprag clutch) that allows the engine to spin the drive shaft, but does not allow the drive shaft to spin the engine. That one-way drive is a necessary precondition for an automatic gear change, and there are sprags like that in automatic transmissions, too. If you accelerate past the overdrive governor's cut-in speed of (nominally) 27 mph, the governor will send current to the solenoid, and call for a shift INTO the overdrive gear. But that shift cannot take place until you momentarily slack off on the throttle, which unloads the gearset, and lets the solenoid do its thing. Once actually in the overdrive gear, it will stay there, unless you let the car slow well below 27 mph, and also slack off on the throttle, as you would when pulling up to a red light, for example. The other way to get it out of overdrive gear is to kick it down, meaning you floor the gas pedal. When the pedal hits the mat, the linkage also hits the kickdown switch, which does two things: first, it interrupts the current going to the solenoid, and second, it shorts out the ignition points via a grounding contact in the solenoid. That causes the engine to stop delivering torque for a fraction of a second, just long enough to take the pressure off the gears in the overdrive unit, and allow the solenoid to withdraw. Bingo! You are now in direct drive, with the throttle wide open, and you can pass that blue-haired granny doddering along at 65 mph. Mechanically, the overdrive is now in exactly the same state as it was when you first crossed the 27 mph threshold; it's ready to shift up into overdrive, but cannot until you slack off on the throttle again. The effect is exactly the same as passing gear in an automatic transmission.

    The overdrive mechanism contains mechanical interlocks intended to prevent the curse of engaging two gears at once. Engaging reverse gear forces the overdrive shift rail back, which locks out the sprag clutch, and also prevent the solenoid from moving the pawl. When you are driving in overdrive gear, the solenoid has pushed the pawl in, which prevents any movement of the shift rail, which should preclude shifting the main transmission into reverse, and also should prevent one from fully pulling out the T-handle. You just experienced that lockout working as it should.

    The governor is the "brains" of the overdrive, and is what makes it automatic. Bypassing it with a toggle switch destroys the automatic feature, and turns the overdrive into a sort of "high range / low range" affair like a 4X4 transfer case.

    You should probably try to meet up with a member who has a car with a normally-functioning overdrive, and drive it to learn how overdrive is supposed to work, as designed by the factory. It really is slick.

    Leave a comment:


  • 62champ
    replied
    Originally posted by Studebaker1965 View Post
    StudeRich,

    I read your explanation and it was very helpful. If I pull the handle out of overdrive, am I then safe to park in any gear without the car free-rolling? I don’t want my 37 Dictator with the modified overdrive unit from Jerry Kurtz to roll away.

    nate
    Best practice I was taught when I started driving Studebakers 30 years ago was to always put the transmissions in reverse and there is no risk of rolling anywhere when parked. Good luck.

    Leave a comment:


  • Rafe Hollister
    replied
    Thanks for the advice, especially about reverse. Today I was in OD, stopped the car, tried to put it in reverse but it would not shift. Then I took it out of OD and reverse worked fine. I can keep my car in OD all the time, just did 25 miles today, freeway, stop lights, all gears and neutral, stayed in OD the whole time. Maybe that is what the toggle switch does? I will check tomorrow to see if it comes out of OD on its own. My car is in really rough shape, busted windows, won't roll up, guage lights out, nor drivers door lock, no back seat, so perhaps my OD question was a bit premature on my priority list.
    But on the good side, my cars has good brakes, hd front sway bar and rear too, R3 exhaust manifold, dual exhaust, edelbrock, etc... it is deffinitely a hot rod Hawk.

    Leave a comment:


  • Studebaker1965
    replied
    StudeRich,

    I read your explanation and it was very helpful. If I pull the handle out of overdrive, am I then safe to park in any gear without the car free-rolling? I don’t want my 37 Dictator with the modified overdrive unit from Jerry Kurtz to roll away.

    nate

    Leave a comment:


  • gordr
    replied
    You absolutely can lock out overdrive using the T-handle while the car is moving, but ONLY when the car is in direct drive. When kicked down to 3rd direct, as when overtaking traffic is good, or when the car has dropped below the cut-in speed, and an automatic downshift to direct has occurred. Feed it a little gas to take up slack in the overrunning clutch, and then pull the T handle. This is in the owners manual.

    Leave a comment:


  • 6hk71400
    replied
    When I let off the throttle and the car shifts into overdrive, it is a silent almost imperceptible smooth shift into overdrive, at the lower speeds. At higher speeds as you mentioned the change is around 1,000 rpm and suddenly, everything is nice and quiet while cruising.

    I looked at a 47 champion a few years ago. The owner has said that he changed to 12 volts. I asked him about the overdrive. He said, "What's that? i looked under the hood and showed him where the kickdown was supposed to be but missing. I showed him the relay and tried to explain how the system worked. Later on, he advertised the car with "Frematic" transmission. All he understood is free wheeling and the longer braking distance needed after he barely kissed the rear end of the car in front.

    Thom, keep plugging along and you will get the hang of it. The pull handle is again to mechanically take the car out of overdrive. Don't do that while the car is moving. You need the electrical connection to be broken to disengage the solenoid to take the car out of overdrive. To take the car out of overdrive mechanically, it must be completely stopped for the cable to be pulled out.

    Again best of luck and you must be having a ball and grinning ear to ear driving your new car.

    Bob Miles

    Leave a comment:

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