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Negative grounding questions

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ichthos

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I should be able to fire up my Bugeye this week after a very long restoration. I decided to make my car negatively grounded, but I am not sure if I did it correctly. I have the negative pole from the battery going to the firewall. I have the positive going to the starter swich. A brown wire is connected to the posiitve cable. I have another lead going from the starter switch to the starter. I have a white/black stripe wire going to the negative side of the coil, and a solid white wire going to the positive side. I have a few questions : 1) Does it sound like I have my car hooked up correctly for negative ground? 2)I read that I need to touch the poles on the generator to make sure it is polarized correclty. I do not know if this car was positive or negativley grounded to begin with, so how do I know if it is polorized correctly? 3) I tried to be very careful when putting in a new wiring harness, but if I have any wire put in incorrectly, will my car simply blow one of the fuses, or will I fry my wires? Any help would greatly be appreciated.
Kevin
 
Polarize the generator by removing the field wire from it (the smaller wire)
Take a heavy wire, hook it to the battery then arc it to the field terminal on the generator 2 or 3 times.
This flips the magnetic fields in the generator.
It is much safer to do it at the generator side rather than at the battery but either end will work but be warned, sparks and fumes from a battery are explosive so spark it at the generator end.
Everything else seems OK from your post.
 
Hi Kevin,
I know you have worked very hard on your BE and I congratulate you for all your hard work. As the electrical drawings can be a bit confusing sometimes, I would recommend you power up your BE for the first time a little at a time, like taking out all the fuses (2 in the original design).
In addition, I would connect a 5 amp fuse in series with the battery and then start turning stuff on, not the starter with the fuse there.
That way if there is a direct short, the fuse will blow rather than melting a wire somewhere. In addition, remeber the lighting circuit is not fused at all on the original design. I couldn't remeber if you added any additional fuses, but I highly recommend it.
Good luck,
Scott in CA
 
Sorry, Scott, but I do not understand what you are saying. My car is pretty much original, so I do only have two fuses. Why would I take out the two fuses if I temporarily have the five amp fuse? Do I just put the 5 amp fuse inbetween the brown wire and the positive cable? Would I then turn on each item (heater, lights, wiper, ...)to make sure they are working, and then turn over the engine? I admit I am a little nervous about messing things up after such a long haul.
Kevin
 
When you polarize the generator, just a brief fractional second of spark, done 2-3 times, don't hold it on there.
 
Hi Kevin,
The original BE did not fuse the lights or the ignition. If, for example, somehow an error was made in the wiring and a battery plus connection was grounded, a large amount of current will flow. The battery has the capability to flow a few hundred amps. The small wires used throughout the car for the lighting and the ignition will melt. You don't want that do you?
So another way to do this is first take out the two fuses. Turn all the switches off. When the last connection is made to the battery, i.e. the brown wire, just touch it to the post. There should not be a spark. Feel the wire, it should not get hot. If is there is a spark or it is getting how, that means that current is flowing and it should not. Track down the problem. Then repeat.When that is OK, put in one fuse at a time, and check for a warm wire or a spark. If so, track it down and fix. When all that is OK, thenturn on one device at a time and check for function. Continue checking the brown wire to insure that it is not getting hot. When that is all done and you have everything working, then bump the starter with the coil high tension lead disconnect. Turn the engine over without spark until you get oil pressure. Once there is oil pressure reconnect the coil and turn over the starter. If there were requirements to run-in the cam, this is the time. Good luck.
Scott in CA.
 
This is good advice. I replaced the main harness in my '63 and converted to negative earth at the same time and despite my best efforts I had the wiper motor mis-wired and melted the wire to it. It was easy to find the error except for seeing through the smoke. That's not the way to find it!
 
Hard to believe they wouldn't have put fuses for the lights and ignition. I guess part of my not understanding is that I don't understand what the fuses do protect. If I understand correctly, it sounds like putting the 5 amp fuse between the brown wire and positve cable pretty much protects everything except the ignition system then, correct? I do have a cut off switch by the way. So, let's say I have the five amp fuse in place between the brown wire and positive cable. Here would be the steps I take: 1) I will remove the fuses and make sure everything is shut off. I will then turn on my cut off switch. If the brown wire is not hot (and/or the 5 amp fuse is not blown), I will shut off the cut off switch, put one fuse in at a time, and check the brown wire again. 2)Next, I will turn on each control one at a time and check to see that each item works and that the wires to each item are not hot. If hot, I need to correct my wiring connections. Does this sound correct? Thanks for your patience.
Kevin
 
Only thing I'd add is to use a fuse larger than 5A. Headlights alone usually draw more than that. If you have a dead short, it won't matter if you have a 5, 10 or 20; they'll all blow.
 
Hi Kevin,
Because the original BE and wiring harness did not have enough fuses, a simple problem, like a red panel lamp ground out, can cause a big problem. Just because I had a BJ8 burn up in my garage, is not the only reason to believe me. At the bare minimum, I would insert a 20-25 amp in-line fuse holder in the brown wire leading off the battery. That way if you have any short to ground, that fuse should blow and help protect your wiring.
Scott in CA
 
This is my first car I have ever restored. I do not know enough yet to be making improvements. Putting in another fuse makes sense and seems easy though. Are you saying you would you put the fuse in permanently? I know it sounds funny after all my work, but I don't even know how to start the car or turn anything on yet even. I guess I better figure that out in the next week.
Kevin
 
I would leave it in while you check out the electrical system and get the car up and running. If it was my car, I would make it permanently.
Scott in CA
 
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