Packard Forum Index » ZIS, ZIL, and other Packard Cousins!

I have little experience with automatic transmissions - no wonder, in Europe these were taboo for a long time due to their hunger for energy. So I don't know if the following sentence from an operating manual is a misprint and I would like your advice:

"Avoid towing the vehicle at speeds below 25 km/h (15 mph)."

Does that make any sense?

I do not pretend to have any knowledge about Packard automatic transmissions, but I have done a lot of towing and we ALWAYS removed the drive shaft when pulling automatics. The concern was that they would not be properly lubricated as the pumps were from the drive end so having the back end turning from the rear wheels would cause bearing wear and overheating damage due to the lack of lubrication. I never towed one any other way to know if this was true or not, but it was a simple procedure to remove the drive shaft and be safe. Of course if you are using a Tip and Load type transport this is not necessary.
Cautiously yours,
Bob J.

It does seem a bit odd to have a minimum speed as the usual caution when towing a car with an automatic is not to exceed a certain speed or distance. Maximum is 30 mph or 300 miles in Packards case

Packard Ultramatics and several other early automatics do have a rear pump driven by the wheels but capacity is usually much less than the front pump. If it was not a typo, perhaps the mfg who issued the minimum speed caution also has lubrication concerns. It could have a rear pump that needs to be at a certain speed to provide adequate pressure lubrication to whatever parts are turning or if no rear pump, perhaps there is some sort of fall back action set up by a rotating part maybe like a splash lube where slow turning would not be sufficient.

Bob (Bob J), thank you very much for your answer. You obviously have a lot of experiences in towing and certainly good reasons for removing the cardan shaft every time. For the "tip and load type transport" you mentioned, I had to go to Google first.

Howard (HH56), thank you very much for your support. In order to be able to appreciate the content of your message sufficiently, I will probably have to read a little more in the manual. The talk revolves around a Soviet PowerFlite-like two-speed automatic transmission. As you both have already outlined, the manufacturer (ZIL) seems to be concerned with lubrication.

The whole chapter reads:

"It is necessary to monitor the proper operation of the hydraulic transmission and the level of oil in the gear case. When towing a vehicle with a defective hydraulic transmission or with a functioning hydraulic transmission over a distance of more than 100 km, the cardan shaft must be removed. It is allowed to tow a car with a working hydraulic transmission over a distance of no more than 100 km if the transmission control button H (neutral) is turned on. Avoid towing the vehicle at speeds below 25 km/h."

As soon as I know more about the pumps, especially the rear one and how it's powered, I'll get back on the subject.

Here comes another question related to the manual.
"Using the radio in a parking lot with the ignition on is not permitted as overheating can damage the ignition coil."

The mention of the parking lot doesn't seem essential to me, but why is the radio mentioned?

Don't believe it is as much the coil as the points that would be the issue. I speak from experience that if the key is on in the ign position and you sit listening to the radio, when the engine stopped if the points were in closed position current will still flow thru the coil and the points will overheat. When you try to start the car, depending on how badly they overheated or burned the car will run very poorly or will not start at all.

No idea what kind of ign switch the car you are inquiring about has but sounds like it may have been similar to Packards. Packard until the 23rd series 49s did not have an accessory position. The key only turned to one other position so the points and coil were always in the circuit even if engine was not running. Once the switch added an accessory position then if turned to the left, everything would still be energized EXCEPT the coil and points. You could play the radio until the battery died (which was another whole issue) but presuming some juice was left in the battery the car would still start and run.

I had often wondered why some prewar Packards had the radio always powered directly from a hot source and that could be the reason. Don't believe Packard was alone in that either because a scene from the movie In Harm's Way has John Wayne arriving at his quarters to find his housemate's radio in a parked and empty Ford convertible playing. Just like headlights, guess it was all too easy back then to drive in, park and forget to turn something off only to come back and find a dead battery.

Leaving the ignition switch on with the engine not running is likely to damage the ignition points, the coil, and perhaps the ignition resistor if one is present. The battery may also run down. It doesn't matter why the switch is left on, or whether any accessories are on or not.

I have witnessed a situation with an old 6 volt Plymouth where the switch was left on, and after about 10 minutes, the coil burst open with a loud bang and spewed hot oil all over the engine.

As mentioned above, if the points happen to be open, no harm will be done, but if they are closed, which they are likely to be, expect problems if the switch is left on for more than a short time with the engine not running.

Regarding the radio wired to hot:

- You can play the radio while relaxing near the car without worrying about someone hopping in and stealing it, since you have your keys with you.

- Some early radios had separate keys so it wasn't much of a problem being tied to hot, since the radio could not be turned on by passerby of a parked phaeton or the like.

"Using the radio in a parking lot with the ignition on is not permitted as overheating can damage the ignition coil."

Howard (HH56), so in the above sentence not only the parking lot but also the radio is dispensable and used to describe an everyday situation?
I was watching the movie Harm's Way today and saw John Wayne turn off the radio in the parked convertible. Also, a rushing Packard One-Twenty helped win the war in two hours and forty-five minutes.
TxGoat & humanpotatohybrid, many thanks for your additional explanations.





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