Maybe there is a source for a switch that fits well without drilling a massive hole, etc. I would love to see how others have done it instead of reinventing the wheel. I am thinking that the reverse lockout switch could be a thread-in type with a ball that is pushed in by the shift rail in the transmission cover when reverse is engaged. Also, how do you drive yours? Do you split every gear? Do you find you need to be at a certain road speed or rpm for engaging or disengaging the OD? I have read that the shifts are slower at lower speeds since the output shaft of the transmission drives the pump that shifts the OD. This plus the reverse lock-out should keep me out of trouble I think. When the breaker shuts off, the electromagnet de-engergizes and the contacts separate. I think it has electromagnetic contacts that keep it engaged. He reset the breaker without pushing the stop button on the saw and it didn't try to start again until he pushed the start button because it has a safety feature. We were ripping some nasty wood and it bound the blade, tripping the breaker. I got the idea from my buddy's table saw.

Does your setup do this? I am forgetful, so I want to idiot-proof it as much as I can. I would like to set mine up so that if I park the car and shut it down with the OD engaged, when I restart it the OD will be disengaged until I hit the button again. I would love to see a sketch of your wiring setup if possible. The rifle barrel idea is completely inspired. This works real well, gives great mileage, etc. I assembled a set of 5 small Bosch relays to create a latching relay system, so that hitting the momentary switch engages the OD, hitting it again, disengages the OD. I had it chromed after welding and no one can tell the difference unless they know what to look for. 22 cal rifle barrel and ran the trigger wires down thru the barrel, exiting just before top of the transmission tower ( the rubber boot covers it). Then I have a momentary switch installed in the shift ball (A Volvo shift ball), to actuate/engage the OD. On my car, a 32 Ford, to wire the OD ( A Gear Vendors unit, similar to the Volvo stuff), I used a 60's OD handle and mounted it to a 2 position push/pull switch with an LED so that when the handle is pulled, the led illuminates and the circuit is completed so that the OD MAY be engaged (kinda like an arming switch). I don't know how it would be done on a Model A, but someone has done this, I'm sure.įor my car, I'm using a different transmission case and the shift tower has a backup light switch that I used to disengage the OD. Located in the shift tower itself actuated by engaging reverse. The best way to handle the reverse lock out would be to use a switch The speedometer comes off the OD, so no adapter/reduction is needed.

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