Technical 6 volt OD solenoid

I've read a few of the previous threads and cant get a definitive answer. Hoping there's more info available...currently running a 6 volt system and am considering the 12 volt conversion. Was set to pull the trigger on the parts and remembers the OD solenoid. Looks like I can get a 12 volt version for about $250 in the interweb but damn...that's a lot o scratch. Read a few threads that make mention of a conversion but cant find any vendors that will do this and if they do, is it any cheaper? Also read a few HAMBers that are running a 6 volt solenoid on a 12 volt system without issue. Would hate to burn out the 6 volt version if I can pull it and get some $$ for it after the 12 volt is installed.
Anyone have any strong opinions about best way forward? Thanks in advance...
Michael

 

Run the 6V unit. I know guys that have done so for years. No guarantees, but if it burns out you needed to buy a new one anyway.
You won't get too much $ for it trying to sell it used, which is the same reason you should run with it and start shopping for a used 12V unit.

 

Or put a voltage drop resister on it like you would for the dash instruments.

 

No problem with it been that way for 19 years now.

 

Once again...the HAMB to the rescue!

 

A 6 volt solenoid can live a long and happy life on 12 volts. All the solenoid is is an electromagnet that moves a plunger to engage the OD, not that different from a GM starter solenoid. You're not going to burn anything up, it's just an electromagnet that you turn on and off.

 

If you are really worried about burning it out, You can put a dropping resistor in series with it, and it will ensure it will only ever get 6 volts. If you can measure it's resistance or it's current draw (on 6 volts), the value of the resistor can be calculated. The resistor will get warm to hot , so it would need to be mounted in the airflow under the car.
Starter solenoids work OK on 12 volts, because they are only on for a few seconds at a time.
Your overdrive solenoid may be on for a couple of hours in one hit, I wouldn't like to run it for an extended time on 12 volts as it will probably burn out real quick.

 

Quick follow up question...anyone have experience using Runtz for 6v dash gauges? I've seen a few threads that they can get finicky about connections. Also saw a kit that included a terminal block of some type that all gauges were wired into and the voltage was regulated from there.

http://www.vintageautogarage.com/1949-1953-Ford-Mercury-Car-Truck-6V-12V-Conversion-p/f4953612k.htm

 

The initial throw on the solenoid draws a lot of current (it's fused at 30 amps 6V) so that's going to put a lot of stress on your proposed voltage reducer. On the other hand, if you reduce the voltage too much, those solenoids don't like to throw with anything less than 6 volts.

I think I'd try one of those generic ceramic ignition ballast resistors and see if it works.

 

Like the used car salesman would say,"Trust Me"... you need to do nothing!

 

slopok is right on this i myself have ran the 6 volt on one of my cars for 12 years the merc has had one since 95 still works fine. i do have a backup one in the parts bin but hell it might be there when they plant me.

 

Check with Fifth Ave Garage,HAMB vendor...

 

I converted my '55 Ford 2 dr wagon to 12v and the O.D solenoid lasted about a month. They are already old and tired, expect the worst on 12v. I would look into some kind of voltage reducer.
Watch for ads for 3 spd/OD trans on CL and other places, I bought a whole trans with a good solenoid for $50. My '31 Tudor has a '56 Chevy truck 3 spd/OD in it. Cheap overdrive, worth the effort.

 

Follow up question to my follow up question...thoughts on keeping the 6v version of the OD relay? Seems like that might burn out in a hurry but maybe it will last like the solenoid as its not used often? Also, I've got a 6v electric fuel pump. Other than it throwing more fuel downstream, any reason I need to change that out for a 12v version? Thanks.

 

I think I'd change the fuel pump. Throwing more fuel downstream is not a good thing, not to mention a broken fuel pump will leave you stranded on the road compared to a broken overdrive.

 

I agree, don't know how long a fuel pump would survive on 12 volts.

 

I am in the process of installing a T90/D18 with the BG overdrive and I asked Herm The Overdrive guy the same question on monday. He said the solenoid doesn't care 6V or 12V.

http://hermtheoverdriveguy.com/