Packard Forum Index » V-8 (1955-56)

Hello,

Are in thinkings of conversion electrical system
from +ground to -ground what needs to be changed ?

Anyone who have the experience, kindly let me know.

My car Packard 1955 Four hundred with torsion level,
https://packardinfo.com/xoops/html/modules/registry/index.php?Action=view&ID=581

Thank you!

Regards
Mikael Ohlson :)

Why?

Generally nothing except repolarizing the generator and switching the leads at the AMP gauge if you have one. Other then that, nothing is polarity sensitive on the packards unless you have a solid state vibrator in the radio.

Hello,
Thank you for responding so quick :)
Because of the reason to put in a modern alternator and easier with accessories.

best regards
Mikael

I've done this conversion on my 1955 Patrician. In addition to the generator repolarization (described in the service manual) and ammeter leads mentioned above, you should also switch the leads on the spark coil.

Craig

Hello,
Thank you for responding so quick :)

I do have a radio but ot of order so no worries. I was thinking on torison level but if not polarity sensitive so am I happy. Sounds very good just AMP/volt meter and generator not starterengine need to be switched? I noticed Craig respond about ignition coil, thank you.

Regards
Mikael

Original non-transistor Radio, starter motor, Torsion-Level motor and fans do not care about polarity.

I switched mine to negative ground in order to install MSD electronic ignition and a modern stereo radio/CD player.

Craig

Hi,

do you think you can advise page or link in service manual I have tryed to find but are not able :(

Thanks in advance :)

Regards
Mikael

I forgot to mention that you should check the voltage regulator for polarity capability. Some are positive ground only, some are negative ground only and some are OK either way. On my 1955 Patrician, when I polarized the generator for negative ground, the voltage regular "went up in smoke" when I ran the engine. I went to a local auto parts store and bought a regulator that would work with either polarity and then everything was fine.

To polarize the generator after the polarity has been reversed (now negative ground), quickly short between the "BAT" and "GEN" connections on the voltage regulator. See "Installation of Regulator" paragraph on page 14 of the "Electrical" section of the Service Manual. Here's a diagram for a John Deere tractor, but it's the same as your Packard:



Craig

Chances are that your alternator will have a built in regulator so you won't have to worry about that.