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  • #16
    Some early British sport cars had this setup with a toggle on the floor shift, the toggle would interrupt the ignition for 1/50 of a second and the OD would shift down with flooring the throttle. The toggle is an interruption type where the switch is momentarily opened then closed again when switching. It does the same function as flooring the throttle. The OD is engaged the same as conventional, however when in OD if you see ahead that you may need some added performance flip the toggle and you are instantly in conventional. There are multiple configurations of toggle switches that perform multiple purposes, they are not just on and off. I have switches with two, four and six terminals and spring loaded. Who knows the design and purpose of this "toggle". I similarly wired an overdrive with a push button in lieu of the conventional kick down do shift down when desired instead of flooring the throttle. No manual will help with this, it took several attempts to get what I wanted. The manual was handy to check the OD components but that was all. I never touched the OD lever when rolling as I was scared of a catastrophic explosion. I suppose under power in conventional drive it could be done.
    It doesn't appear that the seller has any idea as to the operation of the "toggle". The toggle switch I show can be wired for many configurations, it can also operate exactly as the kick down switch, while it is moving through center it momentarily opens the coil circuit and will allow the unit to shift down into conventional. This method can allow for five speeds however it takes some dexterity, I could do it easily when I was 17.

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    • #17
      That looks like a DPDT switch, Altair. I remember switches of the same brand being used as ignition switches in old IEL chainsaws. Also worth noting, British sports cars, and Volvos, used the Laycock de Normanville overdrive, which was electric over hydraulic, and not really comparable to the Warner units.
      Gord Richmond, within Weasel range of the Alberta Badlands

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      • #18
        We paid a reasonable price for our new to us Lark because the electrical system was beyond the skill set of the previous owner. We purchased the Lark specifically because it has the BW overdrive, so getting that working was high on the to do list. Adjusting the throttle linkage and enabling the overdrive downshift switch is low on the to do list. So low in fact that before I enable the mechanical switch I think I'd add a DPDT relay and a momentary push button to duplicate the operation of the mechanical switch only at part throttle.

        We owned and operated a 1950 Chrysler with the semi-automatic transmission for 33 years and I never liked forcing the downshift with the throttle. An aftermarket accessory was a push button knob for the column shift that would give you part throttle downshifts.

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        • #19
          OK, this is a lot to digest. I kept trying that link, couldn't get it. Then I noticed that it downloaded a pdf file, so now I can read it. I've been driving the car two days now, and getting the hang of the OD. Last night I put it on a Subaru mechanic buddies lift... what a surprise... R3 cast iron exhaust manifolds! He had never seen an OD. Fun.

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          • #20
            Art, I don't want to get too far off Topic into Chrysler's as has already been done on Brit Cars, but just remember that your situation with your Studebaker will be about 83% Different than with the Fluid Drive, it actually did a Major Gear ratio Change, the BW Overdrive Ratio shift from O.D. to direct is very slight, not even roughly comparable.
            StudeRich
            Second Generation Stude Driver,
            Proud '54 Starliner Owner

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            • #21
              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

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              • #22
                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.
                Gord Richmond, within Weasel range of the Alberta Badlands

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                • #23
                  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

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                  • #24
                    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.

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                    • #25
                      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.

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                      • #26
                        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.
                        Gord Richmond, within Weasel range of the Alberta Badlands

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                        • #27
                          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.

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                          • #28
                            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?

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                            • #29
                              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.
                              Gord Richmond, within Weasel range of the Alberta Badlands

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                              • #30
                                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.

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