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Polarizing a Generator

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vping

vping

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How do you this for a '67 B? I am trying to get one running and not sure if the car is negative or positve ground but I believe it's still positive. If I understand it correctly, you can install the battery positive or negative but only the Generator is something that has to be worried about. Are my assumptions correct?
 
The tachometer will fry if you don't convert it before switching polarity. Otherwise polarize the generator (and some argue the control box as well) and you're good to go.

There are many ways to polarize a generator, but here is how I do it (clipped from my web site)...

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Whenever you install a new generator, it must be polarized positive or negative ground to match the car's wiring. To do this, use the following procedure.

1. Connect a length of 14-Gauge (or similar) wire to the 'A' terminal of the Control Box (voltage regulator).

2. Quickly swipe the opposite end of the wire two or three times across the 'F' terminal on the back of the generator. The 'F' terminal is the smaller of the two. There should be a small spark.

DO NOT CONNECT THE WIRE TO THE GENERATOR or leave it in contact with the generator for more than a split second. Avoid touching the wire to anything else.

3. Enjoy your car.[/QUOTE]
 
That will be very helpfull but I'm now a bit concerned about the battery hood up. I am getting this car running for a friend and he is not sure if it was Pos or Neg. The terminals are the only thing I have to go by but not sure if that tells the whole picture. The car is still set up for the old screw type terminals and two 6's. I have a new 12V and there is only one way to hook up with one being a large post and the other being the smaller. This is how I decided to hood up the battery - based on battery post size.

Is this a bad way to decide? How else can I tell how the car was hooked up?
 
Vince - "The car is still set up for the old screw type terminals and two 6's. I have a new 12V and there is only one way to hook up with one being a large post and the other being the smaller. This is how I decided to hood up the battery - based on battery post size."

That is as good a way as any and at this point just about the only reliable thing you have. You can look at the tach to see if it says positive ground on the face, but that may have been converted to negative ground and the positive ground marking left on it. Also look at the coil, if the car is positive ground, the + terminal should go to the distributor.
Cheer,
 
Yeah, you have to make your best guess and hope it's right. I suppose you could open up the tach and see if it appears to have been converted to negative ground. This is assuming it had been converted when the car was and not left to be fried...
 
The current owner rewrapped all the wiring under the bonnet so I hope he connected it to the coil correctly.
 
You need to cut and reverse the direction of the white loop wire outside the tach also. Thats a easy way to check without taking the tach apart to see if the tach was converted. If its all original behind the tach i would hook it up + ground. Bob
 
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