1941 Rewiring a Series 62 Coupe

[Mark Wheeler #20241]

Hi

I am about to install a new wiring harness in our 41 Series 62 coupe.

I am wondering if I should leave the car as + to Ground or should I convert the car to - to Ground?

If I go down this path what should I change as  e.g. change the Wires on the Amp meter?

Thanks

Mark

[homeonprunehill]

11-23-08
Mark... DO NOT CHANGE from POS. GND. to NEG.GND. You will go thru. life knicking yourself, if you do. Clean the area of the starter and bell-housing where the starter attaches real good and generator, and make sure all of the connections are clean and tight.Good Luck,JIM

[35-709]

I cannot think of any advantage in converting a positive ground car to negative ground; it won't start easier, it won't crank faster, the lights won't be any brighter, and other electrical accessories won't work any better.  It might help eliminate some confusion in the future when hooking the battery up or when attempting to jump start the car but that is all.  Why would you want to do it?     

[homeonprunehill]

11-24-08
Mark-Jeff If you decied NOT to go to a NEG. GND. you will still connect the leads from the car with the charged-up battery or other sourse POS. term. to POS.term. the same witjh a battery-charger.Allways go with P OS.    to POS.  regardless of battery priorty. MARK . Sorry I didn't take time to tell you why it was not a good idea to switch battery priorty, there are two reason...#1 I don't how to type ( PECK & HUNT) # 2 Your trouble will have just started. Let's Start under the hood. NEW coil with neg.gnd. and new voltage reguator and maybe generator. Under the dash,  new inst'ments  maybe a new heater motor. MARK believe-me it will be the start of a new set of problems for you. Good Luck JIM

[35-709]

"Jeff If you decied NOT to go to a NEG. GND. you will still connect the leads from the car with the charged-up battery or other sourse POS. term. to POS.term. the same witjh a battery-charger.Allways go with P OS. to POS.  regardless of battery priorty."

Yes Jim, I am well aware of that.  Problem comes when someone not familiar looks at an installation, sees where the ground cable goes (or positive cable), and automatically hooks the jumper cable from the ground on the jump battery to the "ground" (which is actually positive) on the other battery.  Despite the sparks that fly when making the final hookup, some will persist in keeping the batteries hooked up that way.  Happens often enough.

[Doug Houston]

If you have a good new harness from someone like Rhode Island, You'll notice that the terminals for the ammeter have different size holes in them, because the ammeter studs are each of different thread size, to keep it from being connected bass-ackwards.

Another item, rarely touched upon hereabouts is that polartiy of the ignition coil is critical. The caar won't start well if it's wrong (the pulse at the plug must be negative). The engine will also not run smoothly, and overheat has been traced to an incorrect coil as well.

The generator regulator is made to be used with a positive grounded system, and you'll never fool it. It'll let you know when it quits working.

If you'll still prefer the warm and fuzzy feeling of doing it wrong, have at it.

[Mark Wheeler #20241]

Thanks everyone for your input.

We have started on installing the new harness (from Rhode Island) and am leaving the car as it was Pos to Gnd.

So far everything is going as planned have started to sort the wires under the dash. Having trouble removing the Headlight switch would any one know the trick to getting this out of the dash.

thanks

Mark

[Bill Ingler #7799]

Hi Mark: If you type in   "47 headlight switch removal"    under the SEARCH function at top of page it will bring up my answer to how you remove the switch and a picture to help. 41 switch removal is the same as the 47. If you need more help please email me direct.   Bill

[mark Wheeler #20241]

Bill thanks for the link.

We have got the switch out and are moving ahead again. We have about half of the under-dash area reconnected. I still can't believe that the car still ran with all the old wiring, we have found bare wires all over the place.

Cheers

Mark

[Doug Houston]

It's amazing how many people are running around with old wiring as you've described. It always horrifies me to see the stuff. They're jeopardizing something worth possibly $50,000 to save about $500.00.

I did all of my cars many years ago, and made new harnesses from scratch They turned out beautifully. That was before you could buy new ones. I had spent a few years, designing harnesses for a missile project, then overseeing their manufacture, so making a pegboard and laying up a harness was duck soup.

The only car I didn't do was my 38-90 sedan, so a couple of years ago, I ordered one from Rhode Island. They may be a tad more expensive, but  it's the most beautiful product I've ever seen in wiring harnesses. It's a genuine inspiration to just look at it, they've done so good a job.

One of our guys nearby is putting a RI harness in his '42-75, and everything is dropping in place like it did in 1942!

[Bill Hamilton, CLC#16219]

I'm the nearby guy that Doug was just alluding to. By the way, thanks for the help that day Doug. The Harness from Rhode Island went in very easily, any problems I had were of my own making. The light switch gets easier to install/remove after you have had to do it 3 or 4 times, must be a muscle memory thing. Anyway, I sure feel a lot more comfortable driving the car on a long ride with the new wire under the dash and in the engine compartment. Glad to hear that you decided to go as original. These cars were the "Standard of the World" when designed and if everything is up to snuff (correct wire guage and clean contacts-including grounds) the car will perform very well.

Bill Hamilton, CLC#16219
42-7523