Packard Forum Index » Post-War (1946-54)

the condition of my tank sending unit is absolutely hopeless, and I try to find some replacement. The original one is too expensive (with shipping, tax and my thing beond repair, I will end up at 500$), so that I?ll have to find another solution.

Does anyone know a sender from a more modern car that will fit? I do have one in my storage (unknown vendor) that will fit with an adaptor ring. What is the neccessary resistance between empty and full (I don?t want to ruin the instrument)?

thank you from far away
Michael

If it were just the matter of a resistor it would have been figured out already, simple. I believe the 48-50 gas and temp units are "pulse" units and work on a different principle thus just a resistor will not work.

Unless you use a 51-56 sending unit, dashboard tiny voltage regualtor and a 51-56 style gauge there is no option except to repair your old one

thank you, but what is a "pulse" unit?

my float is rotten, the linkage rusty and fragile like a salted pretzel stick and the head of the unit just a piece of rust, I think there is nothing to repair.

The 22-23 senders are different from all other electrical senders Packard used because they are bimetal instead of resistance. The bimetal type uses a heater to make the bimetal strip perform an on/off action with a set of contacts rather than send out a straight changing resistance value. How long or how quickly the on/off cycle happens is determined by the float moving a cam to change pressure on the strip to determine how quickly the heater can cause the bimetal to open the contacts. The gauge follows along with its heater and bimetal strip moving the needle farther and farther depending on the time the sender contact is in the on vs off position.

One person who also had a rusted and unrepairable sender has been working on finding a replacement for the 22-23 series senders and may have come up with something. If you haven't been following the PAC forumhttp://www.packardclub.org/forum/ check out the Project Blogs and specifically the 49 Packard 8 club sedan blog by Tinman_70. On page 46 of his restoration check out some of what he has come up with. While he has changed the fuel tank, he did some early work with different senders and adapters which would fit the Packard tank.

If you haven't posted there before do the necessary stuff so you can log in and then send him a private message and see if he can give you a current status of his progress. If he has found a reasonable Ford bimetal which would be an alternative to the original with the same on/off working, that is great. Issue for a blanket replacement would be the float arm length because Packard did use two different capacity tanks with different arm length senders. On his earlier work mentioned in some of the early pages of the blog he used a constant resistance aftermarket sender and an adapter to mount it. I don't know how well that worked out since the gauge does not get the cooling off period between on and off cycles in the sender.

Since you are both in the same predicament maybe you can swap ideas.

The "pulse" unit as described in the above post send an intermittent signal on/off and the relationship of the on/off times determines the gauge reading. In all other 35-56 Packard systems there is a winding at the top end of the tank unit with a "wiper" that is positioned by the float arm.

While I am not familiar with the electronics I believe the two are completely incompatible like putting a Crosley rear fender on a Packard to replace a front.

As I said, if it were simple I think it would have been solved in the past 70 years. Yes, someone else on the forum has tried but cries of "EUREKA" have been absent.

I would like to hook up a sender and gauge and measure the interval of the on/off cycle at varying float levels just to see what it actually is doing. If the cycle was found to be relatively consistent or predictable then it might be possible to make an IC timer module that would switch a small relay on and off. Use a common aftermarket rheostat type sender to vary the timer.

I have a sender and just found a cheap gauge with a damaged needle on ebay. If it isn't burned out will see what I can find out about the operation.

It would be interesting to see if a timer could be configured to more or less duplicate the bimetal sender without introducing an error. I agree with Fred that it seems unlikely the constant resistance sender will be entirely compatible. I know Tinman_70 has had his replacement working and reading correctly in short spurts but last time he mentioned it he had not left it on an entire day to see if the gauge would be stable over time. Without being able to have the brief cooling period the off cycle of the bimetal permits I suspect the gauge will gradually read higher than it should. Would be nice to prove that one way or the other.

I worked on an answer for over an hour... but was automatically logged out.. the only fault of this forum is the short login time

all my text is lost and now I will only repeat the consumption

I will go back to stone age and use a dipstick ((

If anyone is interested in the electrical funktions, I will try to explain again

Just joking about the dip stick? If your odometer works, just do as many others with similar problems do and every 100 or 150 miles just stop and fill the tank.

The time out can be annoying and most of us have gotten caught at one time or another. It would be nice if there was some kind of warning but guess it is limits of the software used to run the forum.

While composing a lengthy reply you can periodically do a preview of your writing to change screens and "reset" the timer as one solution. Many have gotten in the habit of selecting the text and doing a copy of the entire reply as insurance if it seems to have taken longer than usual to compose. That way if you get the forum not selected error when you submit the post you can relog in and go thru the motions to get another reply window. Just paste the copied text back into that window and all is well again.

At my job we also use a WEB base data system and as Howard said, doing a copy as you go along, (CTRL A) to select all text and then (CTRL C) to copy, will save in in your memory and you can also post it almost anywhere. Also (CTRL Z) will undo your last command so if you delete text it will bring it back.
Sometimes if your really lucky, just hitting the back arrow on your WEB browser, will bring everything back, but not always.
Wes