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

Agreeing with what JW just said, my '54 (converted to 12v- grnd) starts just fine with the ballast resistor, and no switching at startup.

I would recommend you change the starter solenoid to a 12v version.

Also, don't forget all your bulbs.

on my 12v conversion. they had a 1.5ohm internally resisted coil and then added another 1.5 external. i took all that mess off and bought a 12v 3ohm internally resisted coil from napa. again on my blog i believe. I am running points still.

the starter solenoid on my 37 looks like an original solenoid...it has the push button on the end for remote starting. could it be a 12v replica...maybe. but if not...then i'm running the 6v solenoid on 12v and it seems fine.

if you choose a coil with an external ballast resistor, you can bridge it with direkt contact between the wire going to the starter solenoid and coil +

coil gets undepressed voltage only if the starter is engaged (and voltage is down while cranking)

Thank you for all of the input on this issue. I greatly appreciate the knowledge and insights.

One last question that has been puzzling me: If a Ballast Resistor on the coil can bring the coil voltage from 12V to an 8V operating voltage (after starts), can the same be done for a "primary" power feed to the entire car?

Maybe, I am showing my lack of experience upon this matter, but if a Ballast Resistor was placed upon a "primary" power connection to the car (if existed), this would cause the entire vehicle's voltage would operate on 8V, which would be closer to the factory 6V without requiring Bulbs and gauges to be rewired. (I am probably wrong with this assumption.) This would "in theory" allow the vehicle to operate on "dual" voltages (12V for the starting and 6V for the "auxilaries").

Either way, I am trying to find the simplest (probably not possible)way to complete this conversion.

Seems like a lot of trouble for nothing.
Wes

Short answer is no. A resistor can't handle widely varying loads. It is a fixed resistance value calculated on a known amount of current flow to be sized both for the required amount of voltage drop and the thermal load of that current and voltage drop.

It works for the coil and blower motor because those are relatively fixed loads. Some have used them for radios too as that is also a fairly consistent load. Downside is resistors waste power and get hot so need to be mounted where no damage can occur.

A resistor would not work for the OD solenoid because the solenoid requires a current of approx 20 amps to pull in yet once in reverts to a holding coil which only pulls 2 amps or so. Using Ohms law, If you size the resistor for 20 amps the voltage drop will be different when only pulling 2 amps. Conversely, if you size it for 2 it will most likely burn up when pulling 20. That would be the same problem with a resistor for the whole car because of different amounts of accessories or lights in use.

I agree, Wesley. If the object of the conversion was primarily for more reliable starting, there is really no reason to convert. Any 6-volt Packard in good tune should start very quickly and without problem except perhaps north of the Arctic Circle.

with 12v one can go to any autoparts store and buy parts for it. like bulbs, battery, etc etc.

each side has its pros and cons.

About a year or two ago, I'm thinking some people had a problem with the housing of there starters breaking. The only thing in common was they had all switched from 6 volt to 12 volt. Just saying, any way I person can make an argument for how they want to look at it. So I'll just keep mine the way it is or maybe wait until they go to a 24 volt system because that has to be twice as good as a 12 volt system.
Wes

Good Evening all...I agree with Owen, Wesley, and others who question the necessity the change from 6 to 12 volt. Our 1949 Deluxe 288 Miss Prudence, always starts reliably year round. She is kept well tuned and is used quite often. Good timing and clean points are a necessity. All cables and connections must be always clean and tight...all part of the charm of driving old machines. We do need to think and act like folks did when out machines were new. Ernie