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Hey Gents,

I'm new to the site and Packards, great site here with tons of info (thanks already!).

I am converting to 12v and am wondering if there are wiring harnesses that are better than others for a '51 sedan 200?

Thanks in Advance!

G'day Jason75,
to PackardInfo but sorry I can't help with your queation.

Instead, I invite you to include your '51 200 Sedan in the Packard Owner's Registry.

Any harness that can handle 6v, which has a much higher current draw, can handle 12v so the stock 6v harness or reproduction is fine. I can't speak for aftermarket replacement harnesses, though, so those who've had experience with them will surely chime in.

BigKev did a 12volt conversion on his '54 using a GM coded harness. Information on what he did starts around here. The information on his restoration project is extensive and useful.

Also, some additional info on 12v conversions here, and here.

By all means look thru Big Kev's blog for an excellent report on a conversion. There is another poster who just finished a 49 and while he kept 6v, I believe installed a new aftermarket harness. Perhaps he will see your question and refer you to the pertinent part of his blog on the PAC site. One nice thing on your car is Packards of that year and model do not have many accessories so are very simple electrically and do not need a harness with a lot of fuses and circuits if you are going to keep it fairly stock.

KwikWirekwikwire.com/standard-harnesses/ has an 8 fuse harness which is more than adequate for a stock 200 if you stick with the stock Packard headlight switch with its built in circuit breaker. That breaker alone takes care of headlight, parking, tail and dash lights but may rely on you doing some custom wiring with the new harness in order to feed the bulbs. If you are going to add more accessories such as power windows, door locks, fancy stereos, AC, etc or completely plan on revising the electric layout you may want a harness with more fuses and they have a 14 fuse which would do the job. I have not used their product myself but others have. One thing KwikWire advertises is the use of heavier wire in their harnesses which if there is a chance of the car staying or reverting back to 6v at some point in the future would be the way to go.

Painlesspainlessperformance.com/wc/p.php?s=customall is the other aftermarket harness supplier Packard owners have used. They have a few specialty harnesses with a lower number of fuses which might work. Being for specialty use such as off road or racing they might not be a good choice for ordinary street use though. You can visit both sites and download a manual for the various harnesses to see the typical layout and what their recommended installs look like. I know several of the 55-6 owners have used Painless looms but those cars are much more complex electrically than yours and were 12v from the beginning.

A few things you are going to need to overcome on your car is grounding issues to the lights and voltage supply if you are going to keep the stock radio or if the car has overdrive.

On the grounds, Packard relied on contact in the mountings between various metal parts for a ground path. Pot metal and steel frequently rust or corrode and make for poor grounds where they contact. Perhaps the biggest issue when people report erratic light and particularly turn signal operation is a bad ground. If you are not using a harness with separate grounds be sure and clean any bolt and screw connections between pot metal and a fender. The tail light housings and the entire grill area with parking light housings are notorious for issues. Some have actually added hard ground wire connections between the parking light housings and a fender to avoid the grill path entirely.

As to voltage, there is no comparable 12v version on the stock radio and while there may be an option on the OD, it would be expensive to switch so best to figure how to supply them with 6v. A resistor will work for other things such as the heater motor. The gauges in 51 have their own voltage regulator which can work off 12v or there are individual Runtz converters for each gauge but resistors are not the best method for supplying power to the radio or overdrive. The loads on those items can't be regulated very well with just a resistor. You may want to consider a dual voltage layout using something like a 12 to 6v regulator capable of 30 amps or so output (available on ebay) to run those items. There may also be some additional work needed to connect the turn signals since Packard used a plug for the switch connection going up the steering column which will not be part of any aftermarket harness.

Also be aware that things such as the starter motor may be an issue. While there are those who converted and successfully run a 6v starter on 12v changing only the solenoid, there are others on the forum who have had issues with the starter self destructing because the additional torque and speed caused by the 12v slams the pinion into the end housing and eventually cracks the casting nose piece. Packard nose pieces are different and starting to get harder to come by. For that reason you may want to consider having your starter converted to 12v.

Dear All,

Please accept my apologies for the very delayed response, life got even busier than normal!

@ Ozstatman: Thank you for the warm welcome. My 200 is not in as presentable condition was what I have seen on this board and I didn't think is would be worthy of registering.

Its a "barn find" that I am going to breathe some life back into because I think the car and Packards are great vehicles and a part of the fabric of automotive history and aren't seen often enough.

@ JD: Thanks a bunch for pointing me to BigKevs thread, I learned a lot and really appreciate it!

@HH56 Thanks for the wealth of information: I do not have a lockout knob under dash so I don't believe my 200 has OD. I have the below little list gathered of items that need tended to for the 12v conversion, hope I haven't overlooked anything

Ballast Resistor
New Horn Relay
Replace all light bulbs
New Coil
voltage step down resistor for the clock
Either a motor voltage step down resistor, or fresh air blower motor out of a 55 or 56
alternator
New Starter Solenoid

Quote:
Jason,
ALL Packards are worthy of registering. There are 11 "levels" of Condition which can describe your Packard from the drop down lists in the registration process. One of these will fit I'm sure and, as you return your Packard to its former splendour, you can update the Condition to reflect its current status.

Quote:

DONE :)

Jason, for including your '51 Deluxe Touring Sedan in the Packard Owner's Registry.

My pleasure Sir!