Ford Overdrive Solenoid 6 Volt or 12 Volt ?

S

steve fritz

Well-known member
Would the 10AR108 - 62 part number mean its 6 volt or 12 volt application.
This solenoid fits on 49 to 62 Ford three speed trans , but Ford did switch to 12 volt in 19
56. Does anybody have the solenoid application list. No Ford part numbers stamped on the housing , only the manufacturers number 10AR108-62. Thanks for checking.
 
When looking for BW od solenoids, 6 volt units will have no voltage markings.
12 volt units will be stamped , 12 volt, on the end bell (cover).
 
New ones are available for the most common types that have a 1-inch length shaft. 5th Avenue Internet Garage carries them as well as others but many times the units just need the points cleaned. The 10AR10B-62 is a 6-volt unit but many folks use them on 12-volt vehicles. They likely just actuate a bit faster on 12-volts. Look for a 1AR10H-62 or a 1AR10K-62 for 12-volt on the old ones. Borg Warner had part numbers and the auto manufacturers had their own part numbers. The odd ones with 1.5" and 2" shafts are harder to source.
 
How well a 6 volt solenoid will work on 12 volts depends on it's condition. A continuous diet of 12 volts can eventually damage it.

On the new ones, if you go that route, don't assume it's set up properly out of the box. Remove the cap and check that the heavy pull-in coil disconnects the instant the plunger fully extends. If it doesn't adjust it until it does. Having both coils hot for very long will fry the windings around the electromagnet, rendering the solenoid inop. Ask me how I know
 
Dobie Gillis said:
How well a 6 volt solenoid will work on 12 volts depends on it's condition. A continuous diet of 12 volts can eventually damage it.

On the new ones, if you go that route, don't assume it's set up properly out of the box. Remove the cap and check that the heavy pull-in coil disconnects the instant the plunger fully extends. If it doesn't adjust it until it does. Having both coils hot for very long will fry the windings around the electromagnet, rendering the solenoid inop. Ask me how I know
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Funny you mention this. Last week, my OD quit working, and the charge gauge was heavy on the discharge side. This happened after letting the car idle for 20 minutes, was a warm day. I pulled the fuse as I had a half hour drive home. Got home fine without the OD. Next morning, started the car with fuse intact and the OD works perfect again. I suspected the solenoid got "stuck", and what you described sounds like my problem. So, I should make an adjustment on that solenoid so it disconnects closer to the end of its travel, correct?
 
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The pull-in coli should disconnect the instant the plunger extends. The plunger extends very fast, so it will be at the end of it's travel in the blink of an eye. What you don't want is for both coils to be energized for more than the time it takes for the plunger to reach full travel.
 
Ok, well I took the solenoid off and on the bench it worked fine, but the one set of points looked dirty/corroded a bit. These are the points that are closed until the solenoid is in "pull-in" mode. Cleaned both sets of contacts. I don't have specs on what kind of adjustments should be made, so I put it back in and it still works fine. Kind of puzzled why it fails when it gets hot. Happened last fall once or twice but went away on it's own.
 
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The internal windings could be beginning to fail. If that's the case you should get a new solenoid since the windings can't be repaired economically. I've had solenoids do the same thing and they eventually ate the bag.
 
I was afraid of that. Have a road trip on Saturday with the car, I'll see how it performs and I have a spare solenoid if that one continues to give me trouble.
 
It may have a governor problem. The governor is what activates the system when the car gets up to on speed. It has a set of flyweights that close or open a set of points. It's not a common thing but nothing lasts forever. Early set ups have a switch on the transmission that is controlled by the shift rail. When the car is either put into reverse or locked out with the control cable, the switch opens the solenoid circuit. Ford felt they were redundant so they discontinued use of the switch in 1951 or there abouts. I always felt that the switch was a good thing to have but they can fail too eventually.
 
rotorwrench said:
It may have a governor problem. The governor is what activates the system when the car gets up to on speed. It has a set of flyweights that close or open a set of points. It's not a common thing but nothing lasts forever. Early set ups have a switch on the transmission that is controlled by the shift rail. When the car is either put into reverse or locked out with the control cable, the switch opens the solenoid circuit. Ford felt they were redundant so they discontinued use of the switch in 1951 or there abouts. I always felt that the switch was a good thing to have but they can fail too eventually.
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I had the governor apart last summer when I installed the OD in my car. I cleaned the points in there, tested it with a drill and ohmmeter. Has worked fine as far as I can tell. It's just strange that when I was letting off the gas to engage the OD, the charge gauge went hard into discharge, and it just freewheeled at any speed. I would pull the fuse and I could drive normally in all three gears. Next morning it works fine. Happened last year a couple of times and after going through the Ford troubleshooting steps, I cleaned some connections (which looked perfectly clean anyway) and it seemed to work after that. Starting to lean towards the solenoid going bad, but not totally convinced yet.
 
Dobie Gillis said:
How well a 6 volt solenoid will work on 12 volts depends on it's condition. A continuous diet of 12 volts can eventually damage it.

On the new ones, if you go that route, don't assume it's set up properly out of the box. Remove the cap and check that the heavy pull-in coil disconnects the instant the plunger fully extends. If it doesn't adjust it until it does. Having both coils hot for very long will fry the windings around the electromagnet, rendering the solenoid inop. Ask me how I know
Click to expand...

This sounds like solid advice but what happens when you pull the cable out? it looks like when you pull the cable out the fat part of the "shift rod" will not let the "block" move into the ring. This looks like it would keep the solenoid from full travel outward so it cannot activate the switch that disconnects the pull coil. I see on some models there is a switch at the end of the shift rod that prevents this but I have two T85 transmissions from Fords that do not have this switch. How does the coil not burn out when the cable is pulled out? I ask this because I'm installing an overdrive unit in my car and I want it to be trouble free.
 
Hmmm. On re-reading what I wrote I should have said "the instant plunger moves". That disengages the pull-in coil before the plunger reaches full travel.
 
so are you saying that the "pull coil" cuts out so soon that it may not be energised when the shift rod is blocking the travel of the plunger?
I guess first of all I should ask if I'm correct in my thought that when the shift rod is moved to the rear by pulling the cable, the plunger cannot move into the ring? It looks like the plunger travel is stopped by the fatter area of the shift rod. And to me, this limiting of the travel could keep the solenoid from traveling far enough to allow the "pull coil" to be turned off.
But it sounds like you are saying the switch in the solenoid can turn off the "pull coil" before the plunger contacts the fatter area of the shift rod. Is that correct?
I just don't want to burn up the solenoid.
 
I hear that they stopped using the switch at the end of the shift rod sometime in the early '50's it seems to me that this switch would solve this "problem" of the coil being energised while the cable is pulled. So either the "pull coil" is switched off by the limited travel the plunger has with the cable pulled or the "pull coil" is not damaged by staying energised.
 
The "pull coil" releases, or should, when the plunger begins to extend. The lower amperage hold-in coil remains energized and is sufficient to make the plunger complete its travel when you lift off the gas, allowing the drive plate notch to capture the pawl. You are correct that when the OD is locked out with the cable the plunger can't engage with the drive plate. The purpose of the "pull coil" is to get the plunger moving against the spring load that holds it in the retracted position. The moment the plunger begins to move the pull coil disconnects, leaving only the hold-in coil in the circuit. Both coils are energized until the pull coil disconnects regardless of OD shift lever position. Damage occurs when the heavy amperage pull coil remains energized all the time.
 
Mine has NEVER worked in 2nd gear for some reason. Had a time or two where OD in 2nd gear would have been handy.

FYI; using mine on a Model-A
 
As I mentioned a few months ago in a post above, I've been having problems with my solenoid not working and straining the generator on rare occasions. Well, it became a not so rare issue and thankfully I obtained another 6 volt solenoid lately. I've installed it and will see how it behaves the rest of the summer.

I got the "new" solenoid from the local auto wrecker. It was in a 52 Studebaker Commander Coupe and I grabbed the whole transmission, relay with wiring and kickdown switch/linkage. Took the cover off the trans and it was in super nice condition inside, I suspect was rebuilt not long before the car was parked/abandoned.

What is the going rate for a used Borg Warner OD these days? I don't want to give it away, but don't want to rip anyone off either.
 
Gene F said:
Mine has NEVER worked in 2nd gear for some reason. Had a time or two where OD in 2nd gear would have been handy.

FYI; using mine on a Model-A
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Hey Gene,

I don't profess to be an expert on these OD transmissions (yet) as I've only been using one for over a year. However, I do remember when I first installed my OD, it would not work in second gear. The governor I used at that time was a 4 screw cover(out of a 53 Dodge). I took it apart, and it had a way to "adjust" the kick in speed. If I remember it right, there was a flat metal part that would bend under stress from the weights and would make the electrical connection. There was two notches for it (sorry I don't have pictures) and one of them made it engage at a lower speed, on my car with 3.54 gears it was around 35mph instead of around 45mph. It was much better, but I've since switched to a governor meant for the ford trans. (3 screw cover) It engages about 25 mph which is excellent and I love the OD shift in second gear.

I'm curious, do you know what rear gearing you have? That would affect what rpm the governor engages, but also, you may be able to adjust your governor if it's the 4 screw design. I don't recall if the 3 screw unit was adjustable or not.

Hope this helps.
 
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