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

You mentioned that you had the "ground strap" running to the negative side of the battery? Was that the way it was when you got the car? I presume you got a new battery, are you sure you put it in the same way as the old one? The battery in your photo is symmetric to positive/negative, so it would be easy and natural for you to put it in with the negative going to ground, but originally these cars were built with positive going to ground.

On the other hand, this car may have been converted to positive ground in order to power that aftermarket fuel pump.

Many things are NOT polarity sensitive - the voltage regulator, the points and ignition, the lights. Things that are polarity sensitive - the generator, which would need to be re-polarized. I mention this because I think you had the generator rebuilt, I don't know if they re-polarized it as part of that process.

If I understand it correctly, the starter is NOT polarity sensitive, but just in case you want to make sure the engine is turning clockwise when viewed from the front.

Starter does care about polarity.

The ground strap originally ran between the + on the battery and attached to the engine on one of the water pump bolts, I believe.

On some cars, there was a secondary strap between the transmission and the frame.

If you running 6v, make sure all the cables are the thicker 6v variety. Way too many have been replaced with the thinner 12v variety over the years, which creates all kinds of hard starting problems.

Some info for those not too familiar with Packard and the electric motors they used.

Original starters and in fact, most if not all Packard original single direction motors do not care about polarity as they are wired internally to always have the armature and field coils retain the proper magnetic relationship for the desired rotation. If polarity switches externally the internal magnetic relationship also changes but wiring connections between the field and armature ensure they both flip at the same time so rotation is constant. Evidence this by the many accidental and some intentional changes from positive to negative ground where nothing amiss is noted.

While they did use a couple of conventional reversible motors that need special switches or relays to change direction, for the most part Packard reversible motors work somewhat differently. MOST reversibles that Packard used had two wires and the case mounted to body metal provides the ground. On those motors ONLY ONE WIRE at a time is connected to power. To reverse direction, the first wire disconnects and the other wire gets the power. Those motors are also not polarity sensitive.

If the car has a replacement permanent magnet starter such as the mini torque used with one of the Bendtsen adapters or any other permanent magnet replacement type motor which have mostly replaced field coil motors in modern cars, those are most definitely polarity sensitive. Only the armature has coils and those coils will reverse magnetic attraction if polarity is changed. With the permanent magnet field staying the same and armature reversing, those motors will run backwards with a switch in polarity.

Sorry, I meant to say does NOT care about polarity.

Yeah so when I started working on the car that's the way it was set up I'm pretty sure it's still the original 6 volt system it does have a six volt battery and my boss who owns the car likes to keep things original and if he bought it I'm pretty positive that it was the original six volt system so if I'm understanding you guys correctly the ground strap running from the block should be on the positive battery post and the starter cable should be on the negative battery post if that's the case then the battery is in backwards so if I actually took the battery and you know hope the the ground strap up to the positive and the starter up to the negative would it hurt anything I mean would it be fine and yes it is a 6 volt battery and the starter was rebuilt not the generator though that probably needs to be done too

Hey what's with all the electrical tape wrapped around the wires you do that just for like insulation or to keep them okay

Quote:
The purpose of any kind of loom wrapping is to keep all the wires more or less in a neat bundle tightly controlled so there is not a jumble of loose wires all over the place. This helps in installation of the loom as well as allow for a few well placed clamps to guide and keep it neat on the sheetmetal.

If the wrapping is actual sticky on one side electrical tape then an owner has most likely applied it to keep wires together or maybe do a repair. Up until the late 40s early 50s the harness was made of mostly fabric covered rubber wire and covered over all the wires was a braided cotton thread jacket.

That braided fabric cover and wire was superseded by vinyl insulated wire and what is called harness wrap which looks like black electrical tape but has no adhesive. It is just wrapped around the wires and when an end point is reached the end of the wrap is tucked under a couple of the wrap layers and everything pulled tight to keep in place. There may have been a period where fabric covered wire was still in use but covered with the harness wrap.

Heat and grease can make the harness wrap hard and brittle so it sometimes breaks and starts to unwrap. Electrical tape might have been used to keep a spot like that from unraveling more.

You can buy harness wrap from Amazon in rolls about an inch wide or maybe a bit wider.

Kenken,

My car mostly has the original wiring. That has frayed in some places. Until I am able to replace the harness and/or do some more extensive repair like detailed above, I repaired with electrical tape. I realize this is not the best solution, but I have done a pretty thorough inspection and repair of the wiring in the engine compartment and used this method until I find the time to do better.

Yeah no that's fine I wasn't saying anything bad about it I was just curious

"if that's the case then the battery is in backwards so if I actually took the battery and you know hope the the ground strap up to the positive and the starter up to the negative would it hurt anything I mean would it be fine and yes it is a 6 volt battery and the starter was rebuilt not the generator though that probably needs to be done to"

So as has been noted, the car is not polarity sensitive excepting for the generator (reading through it seems the charge/discharge light is NOT polarity sensitive but I cannot verify).

So yes, to make the car original you would turn the battery around, and hook up the ground strap to the positive terminal and the starter to the negative terminal, and make sure the generator is polarized that way.

Here is a little guide for that:

Polarizing your generator

Your Packard has a Delco (GM) system from what I can gather.

I guess I might not quite mess with that yet, if you are SURE you put the new battery in the same as the old battery, it's possible your car was changed to negative ground in order to work with the aftermarket eletric fuel pump that was installed.