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This may be a novice question but My father and I have replaced the engine in my 1954 Cavalier. We are close to getting it started as it will hit but not start yet. We are going over all the wires and noticed the distributer turns counter clockwise. After reviewing a wiring diagram for the 54th series it shows that it has a positive ground. This 1954 Cavalier we are working on had a negative ground system. My question is did some 1954 Cavalier cars have a negative ground and others as positive ground? I'm wondering if you have the grounds switched will the starter turn the motor the opposite way? And finally which way is the distributer supposed to turn, clockwise or counter clockwise. Mine is currently turning counter clockwise. Hope this makes sense. Thanks guys.

The dist does turn Counter CW and most Packards until 56 were positive ground so apparently yours was switched at some point.

The original starters and motors will turn the same direction in either polarity because the relationship between field and armature is hard wired internally. Changing wiring externally will make both change inside and the relationship stays the same. It is the modern permanent magnet type starters and other modern PM motors you have to worry about since the field always stays one orientation but reversing polarity outside changes only the armature polarity inside so it will reverse.

A stock Packard really doesn't care which polarity is used as long as a couple of things are changed to match but if something has been replaced with solid state components, most of those do. Radio solid state vibrators are one example of modern replacement items that will be destroyed with reverse polarity. Electric fuel pumps are also usually polarity sensitive.

Make sure your coil is wired for the polarity you have. If positive ground make the plus on the coil go to the distributor and if you kept the negative ground then the minus goes to the dist. The coil will function either way but the spark is slightly stronger if the polarity is correct.

If you did change polarity then the generator will also probably need to be re-polarized in order to charge the battery properly. That is accomplished by having everything connected but engine and key off. Use a fairly heavy jumper wire to momentarily touch the BAT and ARM (or GEN) terminals at the regulator together for a second or two. There will be a small spark when the connection is made.

Thanks Howard. Maybe I'm looking at this wrong. On my 54 it has a braided ground wire mounted to the side of the water pump and a large gauge wire to the starter. I just assumed it was a negative ground system. How can I be for sure? I pulled this car out of a field and it didn't have a battery inside so I never had anything for comparison. Would it hurt to ground the positive terminal of the battery to the braided ground and the negative to the large cable going to the starter? In my head this sounds catastrophic lol but then again I've never had a positive ground vehicle. This is my first 6V system and I'm learning as I go. Thanks for the info!

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Connecting the braided cable to the battery positive and the insulated cable to the negative would be the way the battery was connected originally. Top post batteries typically have a slightly larger diameter positive post than the negative and most of the original type cables have a slightly larger hole in the terminal going to the positive battery post. Unless the cable has been changed or butchered that kind of gives a clue as to which cable goes where. More modern or universal cables generally have the same size hole so it is harder to tell how a car was originally done.