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Hello Everyone,

Thanks to a healthy dose of ADD, I'm jumping all around on my 2272. Tonight I dug into the R9 OD. My harness is a mess but all the parts are there. I can push & pull the lockout knob under the dash and get into & out of overdrive at a standstill but as I studied the schematics I'm grateful to have found on this site, I see clear as day that they show Positive Ground while my car is clearly Negative. I triple checked this: Neg on battery goes to the block, Pos on battery goes to the starter.

Aside from my OD, all works on my car as expected. What do you all think? Previous owner switched to Neg. Ground? I think the generator can be re-polarized easily enough and bulbs & horns don't care. How about the starter? Am I safe to assume this is currently a Neg Ground car?

More importantly, what's this mean for my OD control? I actually don't mind wiring up a switch or two under the dash for manual engagement if need be but maybe the OD control isn't polarity sensitive either. If anyone knows something about these circuits, I could use a little guidance.

Thanks as always,

Nothing on a stock Packard cares about polarity except the ammeter and to a lesser extent, the coil. If ammeter reads properly now, then someone switched in the past and changed it's connection as well. There is no compelling reason to change back unless you want to for the correctness of it.

If you need repairs to the radio in the future and have to replace the vibrator with one of the solid state replacements available today, that component will care so keep the change in mind if that happens to make sure you get the right one.

The R9 OD is a little more complicated than the R11 electrically but is not polarity sensitive and will work just fine. The biggest issue with the R9 electrically was shorts in the wiring or switch issues which might keep it engaged or cause it to engage inappropriately. If that happened when shifting to reverse or already in reverse, lock up and damage could occur. If your harness is a mess, check or repair it carefully.

There was a retrofit safety switch made available to be installed on cars with R9s.https://www.packardinfo.com/xoops/html/downloads/SC/SC-VOL21NO15.pdf When car was shifted to reverse, the power to OD was completely disconnected so it was forced to disengage. It was a later change but your car may have the switch from the factory. If so, there will be 4 terminals on the backup light switch. 2 terminals next to plunger interrupt power to OD relay and back 2 are reverse light if you have that option, otherwise unused if no light. That might be a good switch to install if you have the original 2 terminal light only switch or nothing at all.

Thanks for the reassurance and good news Howard. Looks like someone did make that change; my ammeter reads as expected and there's plenty of electrical tape on the harness. A little like amatuer hour actually but I'll see about making improvements as I go.

Now, the one type of device I can't get my head around is the relay/solenoid. I'm assuming that a reverse in polarity would have them acting, well, in reverse: pushing instead of pulling, etc. Am I using faulty logic here?

When I'm all done with repairs to the overdrive in this car, I'm gonna post a flow-chart for testing R9 OD systems but here's what I'm thinking: If I ignore the Ground Out circuit at first, I'm down to 3 terminals on the Relay:

1 is Hot
4 goes to 4 on Solenoid
5 goes to Ground

I'm thinking if I get that "machine gunning" from the Solenoid then I'm safe to continue on to the Ground Out circuit, eh?

Thanks,

The relay (or solenoid) is just an electromagnet attracting a piece of iron so doesn't care about polarity in this application. If it were trying to attract another magnet or electromagnet then yes, polarity would make a difference.

To prevent the machine gunning which I recommend you not allow, you need 3 and 4 on the solenoid both at the same time.

When you ground term 5, relay one comes in and applies power from term 1 and out to 4 for the pull in coil. At the same time powers indicator lamp and feeds the coil of relay 2 which is in series with solenoid hold in coil. That hold in voltage goes out terminal 3 to solenoid. Once solenoid pulls in, its internal contacts open the pull in coil and just leaving the hold coil in operation.

One set of remaining contacts in solenoid (term 7) extinguish the indicator lamp when solenoid is pulled in and the other set (term 6) closes and is the starting point for a series of contacts for the ignition cut out. It stays in this state as long as you are in OD.

When you kick down, relay 1 drops out killing voltage to everything, and closes its second set of points which are in the ign cut out circuit (terms 2 & 6). That circuit is now complete so coil is shorted. Engine misses a beat or two and solenoid drops out when torque is released opening the ign cut out points there. If for some reason those fail to open, relay 2 has a slight lag but does open. One or the other contacts either solenoid or relay will open quickly enough to keep the engine from dying. All this happens in a few milliseconds.

Did you get the OD to work?

I have a 47 Packard with non working OD. As I look at the schemtic-it appears that all is needed to check it out is to ground terminal 5(Car off). I have been told by the previous owner the problem is in the OD unit. By grounding #5 it takes out the speed switch. Thus if it does not pull in it is either bad connections or bad pull in solenoid?

If you have 6v at terminal 1 of the relay, then by grounding 5 the solenoid should try and pull in. If it does not, with 5 still grounded, verify you have 6v at 4 and at 3. If you do, then relay is OK and you need to move down to solenoid connections to verify wiring and solenoid.

If there is no voltage at 1 just sitting there, look for a blown fuse (if present) or the safety reverse lockout switch being open.

Ok-when I ground 5 the relay pulls in. I have 6v at 4 but at 3 I have 4.5v. The indicator light also comes on. It also looks like the lockout sw is open. The indicator light does that mean the OD sol is working?

thks

David

Did you hear the solenoid try to energize. Should be a fairly loud heavy click or clunk. The light is on because 4 also is powering the lamp on one side and it's circuit is complete because the solenoid has not energized to the point of opening a contact at term 7 at solenoid. It is supposed to light telling the driver to lift his foot off accelerator so solenoid can move. As soon as it moves, light goes out. No movement could be because the pawl is not in a position to let it complete the stroke or, if you did not hear it trying to energize, the contact inside the solenoid that cuts out the pull in coil when stroke is complete or the pull in coil itself is open. I suspect one or the other because of the 6v vs 4.5. Term 3 is at a lower voltage because the hold in coil is drawing some current and putting a load on it's 6v supply. It is not strong enough to bring the solenoid in alone. The pull in coil doesn't act like it is in the circuit as there seems to be no current draw. The contact does pit and burn & is a periodic service item, the pull in coil could be burned open if the solenoid sat energized for an excessive time without being able to move so the contact could disconnect it.

I think it would be time to verify the wiring and connections are good to the solenoid and solenoid itself. You won't be able to check the voltage at solenoid from the top but If the lamp is on a separate wire at relay terminal 4, you can remove the wires going to solenoid off relay 3 and 4 and make a continuity check using the wires. If lamp is spliced into the loom and only one wire is connected on 4, then you will get a false reading and have to go under to disconnect the wires at solenoid and make the checks directly on the solenoid. It would really be best to do all these checks from below so you can hear the solenoid and also measure the voltage.

Anyway, checking the wire off relay 3 to ground, you should have a short or very low ohm reading. Off wire 4 to ground should be a short. If you have to go under, Look also for a group of black plastic connectors a few feet from the OD connecting that short wiring cable to rest of engine loom. If those are present (may have been removed), they were a source of problems.

If the OD knob is all the way in and lockout switch is open, that could be due to a bad switch or wear on the plunger. Ozstatman just detailed a similar situation with the plunger a few weeks ago and what they did as a quick fix in his running commentary Wades Workshop.

Thanks Howard for all the hand holding.

Resistance of #4 to ground is .3 ohm(I did not separate the 2 wires at #4). Resistance for #3 to ground is 3.9 ohm. I have not tried going under the car. I suspect that something is wrong with the solenoid. What is involved in removing it. I have seen posts with instructions on putting it back in that it must be energized.

The previous owner had Mark Lambert-local Packard wizard-look at the OD years ago-his summation was something in the OD. I am not sure what that means. How reliable is the mechanical portion of the OD?

Again thanks for all your help.

David

The readings are not bad although with the bulb still in the circuit, the .3 ohms on 4 could be the bulb rather than solenoid and solenoid could still be open.

R9's could have mechanical issues if things went wrong electrically. Usual case was if something shorted in that relay 5 string of switches and OD failed to drop out or was still engaged when going into reverse. If this happened, the OD could lock up. Apply more gas or power trying to move with it locked and damage could result. This was the reason for the reverse safety switch to drop all power to OD when reverse was selected. Otherwise, it would seem that OD was in use a lot of years without too many problems. Going to the R11 eliminated the electrical problem because the electrical and mechanical parts are quite different.

If the solenoid has been removed before and improperly installed, it is possible that is the problem. It does have to be energized to catch the pawl but there is also a spacer that has caused problems. It will go on 180 degrees out and all looks proper but solenoid only works if it is in the correct orientation. The EconoDrive training manual can give some guidance on reinstalling if you have not already downloaded ithttps://www.packardinfo.com/xoops/html/downloads/EconoDriveTrainingBook.pdf