skip1954 Posted April 11, 2011 Share Posted April 11, 2011 Did they make a 12 volt govenor for the fluid drive chrysler transmission ?. I am having a hard time getting my transmission to work right, now the transmission shop is giving up. Here in Los Angeles, Calif. it's hard to find a mechanic who works on vintage Chryslers. Any advice would be helpful. Link to comment Share on other sites More sharing options...
Guest Jim_Edwards Posted April 11, 2011 Share Posted April 11, 2011 (edited) Did they make a 12 volt govenor for the fluid drive chrysler transmission ?. I am having a hard time getting my transmission to work right, now the transmission shop is giving up. Here in Los Angeles, Calif. it's hard to find a mechanic who works on vintage Chryslers. Any advice would be helpful.What you need is a voltage step down circuit with sufficient amps out for the 6V governor. You won't likely be finding anything 12V specifically for the car. 12V Cigarette lighter plug in devices are available to support 6V USB devices but I don't know if they have sufficient current handling capability to provide enough amps for the 6V governor. I'd check with a HAM radio shop and see if they can't fix you up. You can also use a commercially available DC to DC Converter like this one:http://cgi.ebay.com/DC-DC-Converter-Regulator-12V-24V-Step-down-6V-100W-/260728825273?pt=LH_DefaultDomain_0&hash=item3cb4a625b9Jim Edited April 11, 2011 by Jim_Edwards (see edit history) Link to comment Share on other sites More sharing options...
Rusty_OToole Posted April 12, 2011 Share Posted April 12, 2011 Last Fluid Drive was 53, first 12 volt Chrysler was 55 so no, they never made a 12 volt governor.Why don't you use 6 volts? It may be the problem is not what it seems. Give us the symptoms and maybe we can help. Link to comment Share on other sites More sharing options...
Guest De Soto Frank Posted April 12, 2011 Share Posted April 12, 2011 The governor won't care whether you run 6 or 12 volts through it... the SOLENOID on the transmission probably will.The solenoid is energized whenever the vehicle is in the lower gear of which ever driving range is selected ( which could be a while ).Not sure how many amps the solenoid pulls, but the pre-1949 MoPar semi-autos had a 30-amp fuse in the circuit ( '49-'53 used a thermal circuit breaker ), so if you were to use a dropping resistor, it would have to dissipate quite a bit of heat....What issues are you having ? These should work fine on six-volts... Link to comment Share on other sites More sharing options...
Guest Jim_Edwards Posted April 12, 2011 Share Posted April 12, 2011 The governor won't care whether you run 6 or 12 volts through it... the SOLENOID on the transmission probably will.The solenoid is energized whenever the vehicle is in the lower gear of which ever driving range is selected ( which could be a while ).Not sure how many amps the solenoid pulls, but the pre-1949 MoPar semi-autos had a 30-amp fuse in the circuit ( '49-'53 used a thermal circuit breaker ), so if you were to use a dropping resistor, it would have to dissipate quite a bit of heat....What issues are you having ? These should work fine on six-volts...I took it from the original post the problem was resultant of sticking a 12V alternator in the car, although that was not mentioned.I don't think a resistor to drop the voltage is a really good idea. Too much heat. One would have to have a huge ceramic core resistor to dissipate the heat. A DC to DC converter is a far better approach if one just has to convert a 6V system to a 12 volt system.Personally, we survived many years with the 6V systems and unless one is doing some modification that requires higher voltage the best idea is just to leave the sucker alone and be happy in the fact a car over 55 years of age is still perking along.Jim Link to comment Share on other sites More sharing options...
skip1954 Posted April 12, 2011 Author Share Posted April 12, 2011 Last Fluid Drive was 53, first 12 volt Chrysler was 55 so no, they never made a 12 volt governor.Why don't you use 6 volts? It may be the problem is not what it seems. Give us the symptoms and maybe we can help.Rusty here's my problem, I had the transmission rebuilt, and the electrical converted 6 to 12 volts (my mistake). Now the transmission works, but doesn't shift up, when the electrical shop did the electrical, all voltage reducers were added as needed, the transmission shop said the voltage was wrong and now the solenoid to the govenor is burned out, I would like to find what should be the right way of reducing the voltage, before buying another solenoid/govenor and giving it to the shop. Now the chrysler is 12 volts neg. ground, any suggestions would be useful, Thanks Link to comment Share on other sites More sharing options...
Guest Jim_Edwards Posted April 12, 2011 Share Posted April 12, 2011 when the electrical shop did the electrical, all voltage reducers were added as needed, the transmission shop said the voltage was wrong and now the solenoid to the govenor is burned out, That is indeed a troubling statement in light of what has taken place. Not to be a smart a$$ but I think I'd be seriously questioning what was done and inclined to just put everything back the way it started out. You may have a mess on your hands that will be nothing but trouble from now on.Jim Link to comment Share on other sites More sharing options...
skip1954 Posted April 12, 2011 Author Share Posted April 12, 2011 Rusty here's my problem, I had the transmission rebuilt, and the electrical converted 6 to 12 volts (my mistake). Now the transmission works, but doesn't shift up, when the electrical shop did the electrical, all voltage reducers were added as needed, the transmission shop said the voltage was wrong and now the solenoid to the govenor is burned out, I would like to find what should be the right way of reducing the voltage, before buying another solenoid/govenor and giving it to the shop. Now the chrysler is 12 volts neg. ground, any suggestions would be useful, Thanks Link to comment Share on other sites More sharing options...
Rusty_OToole Posted April 12, 2011 Share Posted April 12, 2011 (edited) All right. The change to neg from pos ground shouldn't stop the solenoid from working. If you have 6 volt power to the system you should be OK. This could be the problem, the power MUST go by way of the ignition coil because the coil is cut out during the shifts. The engine must be "stalled" this way momentarily for the shift to complete.So, wiring must be stock for the system to work. You say one of your solenoids has burned out, that will need to be replaced. If you can't face changing everything back to stock you will at least have to be sure all the transmission wiring is stock and running on 6 volts including the coil. Polarity shouldn't matter. Then the idle must be set to stock specs of 400 RPM. Too high idle will inhibit shifting. The transmission must be filled with the correct oil, if the oil level is too low it won't work.Those are the basics. Check those things and get back to us if they do not solve the problem. Edited April 12, 2011 by Rusty_OToole (see edit history) Link to comment Share on other sites More sharing options...
Rusty_OToole Posted April 12, 2011 Share Posted April 12, 2011 Just how badly did your 12 volt genius bugger the car up? Did you save the old parts? It may not be too late to change back to 6 volts. You will have to use 6 volts for the coil, transmission, wipers, and radio anyway plus the lights unless you replace all the light bulbs. That means the only thing on 12 volts will be the starter unless you install a stereo.If all he changed was the generator and battery it may not be too hard to change back. Link to comment Share on other sites More sharing options...
Joseph P. Indusi Posted April 13, 2011 Share Posted April 13, 2011 The DC-to-DC converter mentioned above should be able to handle the current required by the solenoid. The specs show that it can handle 15 amps.Another way to do this is to determine the current used by the solenoid when connected to a 6 volt battery. If you have a DC ammeter, you can put it in series with the solenoid and read the amps required directly. If you do not have a DC ammeter, then locate a large ceramic 1 ohm resistor. Wire this in series with the battery and the solenoid. Measure the voltage across the resistor only and this will be numerically equal to the amps being drawn by the solenoid. Now Knowing the current, go to Radio Schack or the net and find some diodes rated at this current. As current passes throug a diode, (solid state) it drops the voltage about .7 volts. Solder about 8 of these in series, cathode to anode and you will drop the voltage from 12 to near 6 volts without a large dropping ressitor. I have done this to small power supplies when I am too lazy to build a voltage regulator circuit.Good luck. joe Link to comment Share on other sites More sharing options...
Rusty_OToole Posted April 13, 2011 Share Posted April 13, 2011 The DC-to-DC converter mentioned above should be able to handle the current required by the solenoid. The specs show that it can handle 15 amps.Another way to do this is to determine the current used by the solenoid when connected to a 6 volt battery. If you have a DC ammeter, you can put it in series with the solenoid and read the amps required directly. If you do not have a DC ammeter, then locate a large ceramic 1 ohm resistor. Wire this in series with the battery and the solenoid. Measure the voltage across the resistor only and this will be numerically equal to the amps being drawn by the solenoid. Now Knowing the current, go to Radio Schack or the net and find some diodes rated at this current. As current passes throug a diode, (solid state) it drops the voltage about .7 volts. Solder about 8 of these in series, cathode to anode and you will drop the voltage from 12 to near 6 volts without a large dropping ressitor. I have done this to small power supplies when I am too lazy to build a voltage regulator circuit.Good luck. joeHow about just using a Zener diode? Or even easier, buy a voltage drop device from one of the hot rod suppliers.The Hot Rod Company - Electrical, Lighting, Ignition Link to comment Share on other sites More sharing options...
Rusty_OToole Posted April 13, 2011 Share Posted April 13, 2011 Skip what exactly was done to your car? Or do you know? If you don't know anything about cars did you get an itemized bill? Link to comment Share on other sites More sharing options...
Guest De Soto Frank Posted April 13, 2011 Share Posted April 13, 2011 (edited) Actually, the purpose of the solenoid on the MoPar semi-automatic is to create a "downshift condition", allowing oil pressure from the pump at the rear of the transmission to bypass the piston that compresses the heavy spring that actually causes the upshift when you have accelerated to about 15 mph and take your foot off the accelerator.When the car is at rest, the governor points are closed. Turn the ignition switch on, and the solenoid is energized. The governor is designed for its points to open at around 7-10 mph road speed, which de-energizes the solenoid, allowing oil-pressure to build up behind the shift piston, which compresses a very heavy spring. The gears don't shift though, because of the acceleration load on the gears. When the driver takes their foot off the accelerator, the load is removed from the gears, allowing that spring to move the shifting fork & sleeve.A properly functioning MoPar semi-auto should upshift w/o any of the electrical controls connected at all. However, it will not DOWNSHIFT until the vehicle speed drops below abotu 5 MPH, and the oil pressure in the transmission dissipates.Try driving the car with the solenoid wires disconnected ( and ends taped to prevent shorting ). If the car now upshifts properly, the internal mechanicals / hydraulics can be assumed to be functioning resonably well. If the tranny still does not upshift, check the oil level ( should be up to the higher pipe plug on the passenger-side of the tranny), and make sure the engine idle speed is set no higher than 400 rpm, as Rusty mentioned.If you're new to MoPar semi-autos, your foot must come completely off the accelerator pedal, and you must "wait for the clunk", which usually takes 2 seconds or so.It is NOT in any way, shape or form similar to an automatic transmission in design or operating function. This is a critical principle.The original Chrysler shop manuals and MoToR's and Chilton's shop manuals of the era all have excellent troubleshooting info on the MoPar semi-automatic.In an earlier post I mentioned that the "govenor should not care about 12 volts"... after thinking about things a bit more, it might be possible for the governor points to become welded closed from the increased voltage and current draw of the solenoid...In the long run, I think you'd be better off to find another mechanic, and get your car back to six-volts, positive ground. They really do work quite reliably when things are in good repair. Edited April 13, 2011 by De Soto Frank (see edit history) Link to comment Share on other sites More sharing options...
Guest Jim_Edwards Posted April 13, 2011 Share Posted April 13, 2011 (edited) Bingo! The problem with the solenoid is polarity. It may not even be fried. A solenoid is basically a magnetic device that either repels or pulls in a "slug" to keep the principal simple. Change the polarity and the coil excitement is reversed. It's identical to an electro-magnet in the sense the coil is either creating a field that repels or attracts. With polarity reversed the solenoid becomes non functional in the sense of the intention of the circuit design.Jim Edited April 13, 2011 by Jim_Edwards (see edit history) Link to comment Share on other sites More sharing options...
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