Converting to 12 volts makes sense but can I keep my 6V overdrive controls (relay, solenoid, governor) by using voltage drop converters? Buying the 12V versions of these would be expensive. The BW transmission came out of a 53 and is going in my 54 behind a 223.

 

You can use a simple dropping resistor in series with the 12 voly supply going to the control.

 

The OD solenoids draw big-time current, especially at pull-in (> 10 amps). A resistor isn't practical. Many people have used the 6v pieces @ 12v for years with no problems; others burn out quickly. I suspect it depends what condition it's in to begin with. Later model cars and trucks that were 12v (including Chevies, Studebaker, and others) used the same OD setup so you can search eBay and on-line for a 12v piece (I would figure on ultimately changing it). Same story for the relay, yours will work, but try to line up a 12v late-model piece. The governor is just a switch, so running at 12v is actually reducing the current through it, no problem.

 

I actually did on my 55 what you are trying to do. As Ross mentioned, th eonly two (of th efour) components that are actually voltage dependent are teh solenoid and the relay.

The 6V solenoid will tolerate 12 volts for a time, but it's life will definately be cut short. The relay will not tolerate 12 volts for any length of time. The governor is a centrifical counterweight type of switch that at certain RPM raises enough to close a contact, and the kickdown switch is a simple pole switch very similar to a headlight highbeam switch without the stops.

What I did, was ran my 6 volt overdrive in my 12 volt converted 55 off a Vol-ta-Drop. It drops 12 volts to 6. The largest of the two models made will handle 12 amps IF it is connected in SERIES across the two output terminals.

Ok now you are asking "what the heck is she talking about?"

Here is the larger Vol-ta Drop unit - they are available at NAPA, C&G, Carpenter, etc:



You will notice that at the top there is a feed in for 12 volt power, and below there are TWO outputs for 6 volt power - both rated at 6 amps. If you run a 12 ga jumper wire between the two terminals then from one of them out to the power terminal of your relay (where the normal power to the system is supplied) it will work just fine.

12 volt components would be best, but they are getting to be difficult to find and expensive. Ford used the overdrive transmissions at 12 volt from 1956 up through (I believe, and Number Dummy Bill may correct me) the early 1970s. He's actually got vehicles with the overdrives and is very knowledgeable about them - he may also be able to find your 12 volt components. I might send him a PM and kill two birds....

 

Julie or others -- can you give me the solenoid winding resistances (pull-in and hold-in) for either a 6v or a 12v solenoid? I have two solenoids, and they were portrayed to me as 12v units at the swap meet when I bought them, but they have no definitive markings.

PS -- there is a gent in PA who rewinds and rebuilds solenoids to either 6v or 12v, not cheap but apparently he does an excellent job.

 

OYE.....let me look around and see if I can find the spec sheets on those - I'll get back to you.

 

I love it when a plan comes together. Thanks Julie and guys.

 

Sorry to be the one to tell you but that OD and all of its components is all junk. For yours and your family's safety you should crate it up and send it to me immediately...It's your lucky day because I'm feeling sorry for you so I will pay any shipping charges...

That's right, you can rid yourself of that junk and it won't cost you a dime...PM me for the address

Thanks in advance.

 

Louie
I appreciate your concern for my well being, I really do. But being the on the edge, risk taker kinda guy I am, I can't part with it. Oh by the way, I hope you have not gone ahead with the 302 swap into that fine 56. I think there is a law against doing that in CA especially when it involves a 223. Happy 4th.

 

Hi Ross,

Getting back to you on the resistance specs on the solenoid. I couldn't find ANYTHING. All the documents I was able to find just said "touch one lead to the positive terminal end of th ebattery and the other to ground. If it engages it is good, if it chatters the hold winding is bad and should be discarded."

I did however find the specs for the relay windings voltages and the point gap spacing.

 

No I haven't, I have some other issues like steering I want to take care of first. Now I'm thinking a Clifford cam, Clifford 4bbl intake and Clifford headers on a rebuilt 223....Just to be different.

 

The smart way to run 6V accessories when you convert to 12V is to tap the battery at 6V and fuse this source at 30A for safety, then use a relay actuated by your ignition switch to created an ignition source for the OD, heater, and radio & wipers and gauges. I have converted many cars to 12V including a '50 Olds, a 32 Ford 5 window, and F1s and F-100s.
The reason a volt-a-drop will not work for the OD solenoid, is that it draws about 120W on pull in which converts to 10A at 12V and 20A at 6V, then upon pulling in it switches to a hold in coil which is about 20W or 1.7A at 12v and 3.3A at 6V. A resistor like a volt-a-drop is nothing but a wirewound resistor in a ceramic case and it most likely would drop too much voltage for pull-in and would not drop enough for hold-in. It is likewise for anything but wipers and heater where volt-a-drops work ok. A 6V tap does not hurt the battery, and when 6V batteries were common, we very often just added a battery in series when we converted to 12V. The OD has a relay, and a solenoid that are voltage sensitive. The governor is just a switch and works on any voltage, as does the kickdown switch. There were so many 12V ODs made, that getting 12V solenoids and OD relays is quite easy. It is much harder to get 6V OD parts. I like running the old gauges (there are just 3 gauges that are voltage sensitive as the ammeter does not care, and most 54 and 55 F-100s have idiot lights instead of gauges, so dealing with one gauge on a 54 or 55 is easiest with a 6V tap. The wipers and heater work wonderfully on 6V from the tap. You can convert the wipers easily with a 12V motor, you only have to slightly modify the output arm to put in a smaller pin to drive the linkage. The heater can easily have a 12V motor put in it. Operating the starter at 12V will not really hurt it. Series motors build up counter EMF so when the starter cranks the engine, it draws more current, and turns the engine faster which then reduces the current drawn. It still draws more current than a 12V starter, but not enough to hurt it unless it has to crank a long time. It will make a lot of engines start easier with the higher cranking speed.

OK, so how to tap the battery? There are batteries made with taps, first of all. All batteries are made up of 2V cells and there are 6 of them connected in series in a 12V battery. So at the connector between the 3rd and 4th cell, you drill a small hole, about a #25, and use a #10 sheet metal screw. Many batteries have plastic over the connector, so you have to grind it out of the way. If you deal with a battery builder, he can do it for you. IMHO, a volt-a-drop has limited use, and I would not use one. All the voltage dropped by a resistor is wasted in producing heat, so your 6V accessories are using their normal amperage on 12v, with that amperage at the voltage being dropped, causing heat, which is why the volt-a-drop is in a ceramic case.

Regards,

Alan

 

Can you just measure the resistance at the terminals on the cap (pull-in coil resistance)?

 

Well here we are again with Alan and his drilling holes in batteries - not only dangerous but un necessary and creates a number of other problems. People stopped doing that (most people) in the 50s.

And congratulations on your math...yes 10 amps at 12 volts is 120 watts. But a 6 volt solenoid drawing 10 amps is only requiring 60 watts. The device is rated for 12 amps at 6 volts or 72 watts output. Hmmm I don't see the problem.

But Alan is right in two respects - first a Vol-ta-drop is limited in its use, is inefficient because it converts excess voltage to heat, and really shouldn't be used. That is of course why folks regularly install them, the high end restoration shops use them, and they have been working reliably for 60 years - but what do they know. And the other incredible idea of tapping a battery in its mid cell of course is the best solution, that's why every battery manufacturer in the US and Canada produces and sells a battery that has a mid post in it for converted vehicles - like not even one. Technological evolution and safety experience be damned, those people don't know what they are talking about.

Alan, read the post. I have already had the installation completed and working with the vol-ta-drop. I put thousands of miles on the 55 truck with a 12 volt electrical system, 6 volt overdrive, and a vol-ta-drop. It did work, it does work, and it will work. It's safe and precludes the Jerry rigged situation that a drilled battery presents. That kind of garbage is just BAD work. And trying to convince others those "slip shod" methods are better is just irritating.

For Ross, I guess you could measure the resistance. I'm trying to figure what that is going to tell you though. I'm not quite sure I'm following you though on measuring at the "terminals"....Those solenoids should have two wires coming from them. I would think that if you were trying to ascertain if they were 6 or 12 volt, you would "pop" them using a 6 volt battery and measure the amperage draw on each. The six volt solenoid should work and the 12 volt solenoid should chatter.

 

Does the ground matter? 6v pos on old system and 12v neg on new? Julie would know I was just curious. Kurt G.