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The hold in coil is inside the solenoid and is wired in parallel to the pull-in coil through a set of contacts. When the solenoid is first energized at the moment you tromp the throttle, both the hold-in and the pull-in coils work to yank the armature outward. That requires on the order of 15+ amps. As the armature reaches the end of its travel it presses the contacts open to cut off the pull-in coil. The amp requirements drop to 3 or 4 so the thing doesn't burn up if someone kept their foot buried on the gas to climb a steep hill or pull away from some wheezing Zephyr.

The same idea was used in the later solenoids but they are pushing the pawl out rather than drawing it in. This was a brilliant paradigm "shift" as it eliminated the elaborate flyweight mechanism in the overdrive in favor of the cheaper electrical governor.

I have R6 in my 41 Commander and it works nicely, but not as smoothly as the later units. And yes it clicks if you push the throttle to the floor before starting the engine.

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Thanks Ross
I must be really dense on this one. So you are saying the two coils are in parallel and when I hit the throttle, the coils are energized. I do not see that parallel wiring in the schematic. The kickdown switch is a N.O. DPST switch, and teh schematic shows the hold in going thru the switch to the ign coil and is activated only when the OD switch is engaged. . Where is that switch? Nothing on the carb linkage and their isn't any switches on the OD lock out cable. It goes down to a mechanical arm located on the right rear of the OD assembly

Like most Packard wiring diagrams -- particularly prewar drawings -- they may depict how something physically looks but as far as function goes they treat almost all switches, relays, solenoids etc as black boxes with nothing but wires going in or coming out. Rarely is anything drawn on a wiring diagram to show things like coils or contacts that are internal in the boxes. For that info you need to go to something like training manuals or aftermarket books.

If you check the solenoid cut away drawing in post #20 of this thread you will see the normally closed pull in contacts which are located inside the solenoid case. The contacts are activated by the small push rod which the main plunger hits and pushes outward as it reaches the end of its travel.

In the solenoid internal wiring diagram shown in post #22 you will see the two coils in parallel. Both coils are fed from the SW terminal and when the solenoid has pulled the plunger in and it hits the push rod, the normally closed contacts in the pull in coil circuit will open and turn off the pull in coil leaving just the hold coil active.

I agree a lot of the drawings depict black boxes. I had to repair the OD kick down switch and relay so know what is in side them. I think I may FINALLY understand how this works.
In the dwg in post 22, the "boxes" depict contact points within the OD solenoid.
If that is correct, the HOLD in solenoid is always on with the ignition and when the governor is at proper speed and torque removed from the OD by letting off on the throttle momentarily, the pawl engages the planetary gear overdrive.
Either the early 39's were built this way, which logically does not make sense to me (why have a solenoid always active with ignition on) or over the years, a switch in series with the hold in coil was removed from my car.
thanks for all the help everyone, think I have it correct now, if not please advise.
If this is correct, I suspect I do have the two coils reversed as after the rebuild and rewiring, I see a large current draw when the key is turned on, perhaps thru the wrong could in the OD

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On either version, the solenoid is not active at all until you push the accelerator all the way down to activate the kickdown switch or, in the later version, put the car in reverse. In typical normal driving solenoid is just sitting waiting for a command to activate.

On the early 39 version, conceivably the solenoid could be active for an extended period of time IF the driver was one who preferred leaving the trans in reverse when parked. I know this practice was taught at one time to give extra insurance against the car rolling. That could be one reason why on the later 39 version, the relay coil was powered from the ign switch so if the ign sw was off the relay could not be energized to bring in the solenoid if the car was left in reverse. On those cars one would assume the length of time the solenoid would actually be energized by the reverse switch would be minimal.

Howard, I do not agree with this or do not understand your comment.
If what you state is correct, I'm cruising along at 30 mph and need to mash the throttle to the floor to activate OD? Foot to the floor deactivates and makes sense, but not to activate it. I do not have the reverse switch on this model

I activate OD by momentarily letting up on the throttle, hear a satisfactory "clunk" as the pawl engages the planetary gear OD and resume driving in OD

Again, thanks for the input!

You are cruising at 30 and the flyweights have mechanically done their job and prepared the pawl for the automatic engagement. Nothing has yet put the car in OD. The solenoid is just sitting there waiting for something to do because on the R6 it has nothing to do with engagement.

Letting your foot off momentarily when cruising at 30 slows the engine but since the wheels are still going at the same speed a mechanism in the OD that has been blocking the pawl from fully entering the sun gear before this point does a quick movement due to the sudden change or difference in speeds. This action clears the path for the pawl to fully engage which it does via a spring to finally put the car in OD. Solenoid is still just sitting there.

If you want to pass a car or have another reason to drop out of OD, you tromp the accelerator, the kickdown switch is activated and NOW the solenoid has something to do which is to pull the pawl out of the sungear that the flyweights and spring had put in so OD can drop out.

After you pass the car and let up on the accelerator to de-engergize the kickdown sw the solenoid drops out and just sits there with the pawl free to move back into the sun gear when conditions are met. The mechanism has it blocked again but letting your foot off the gas does the speed change and pawl is unblocked so spring moves it back in the sun gear and puts the car back in OD. Solenoid waits and does nothing until you want to drop out of OD again.

OK, I agree with most of what you are saying here.

If what you state is accurate, how does the hold-in coil get energized? Per the manual, the hold in coil is used to hold the pawl engaged in the secondary gear plate. Interesting, a few pages later, the manual states that the Hold-In coil is energized ONLY while moving the solenoid pawl in to the stationary gear plate. The purpose of the pull in coil is to assist the hold-in coil while the solenoid is engaging.
Pull in circuit OPENS when the solenoid plunger has traveled the distance and opens a set of contacts internally

The solenoid spring pulls the plunger (hence pawl) out, disengaging the OD

Per the manuals, the OD kicks in when torque on the OD is momentarily removed from the engine when letting off on the accelerator

So still getting back to my initial quandary, what activates the pull in / hold in solenoid initially?

I don't know which manual you are referring to but it sounds like it may be describing the later R9 or R11 OD circuits which do use the solenoid to engage OD. On those units the solenoid is engaged and held engaged to extend the plunger and hold the pawl in the sun gear the entire time the car is in OD. A large spring is used to retract the plunger and pawl after solenoid is turned off when kickdown is needed.

On the 39 only R6, the operation is just the opposite. The R6 solenoid is typically on only for a period of a minute or two and is used exclusively to retract the plunger and pull the pawl out of the sun gear for kickdown or whatever. As soon as that function is over the solenoid is disengaged and springs take over placing the pawl in position to go back in the sun gear.

Except for the R6 solenoid retracting and the R9 and R11s extending the plunger, the basic solenoid electrical operation is identical. Both pull in and hold coils are energized at the same time and both are used to do the job of overcoming inertia and springs to initially move the plunger. As the plunger moves and nears the end of the plunger travel, there is not a lot of moving effort needed anymore so internal contacts open to disconnect the pull in coil to reduce heat and amperage draw which leaves only the hold coil energized to keep the plunger in position. On all three models of solenoids the hold coil is energized anytime the solenoid is on. With the R6 and R11 solenoids only one wire is used to power both coils. The other end of the coils on all solenoids get ground by connecting to the case. The 40-48 R9 solenoid is different and does have a separate wire to power the hold coil but the overall R9 electrical circuit is much more complex and not applicable to your unit.

Probably not worth adding to Howard’s excellent description but it does sound like the 2 methods have been confused.
I believe the R6 solenoid has spring on outside of the shaft making it naturally (not energized) extended and the R9 has an internal spring that makes solenoid naturally (not energized) retracted.
When pawl is extended, in either case, overdrive is operative.