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66 ‘ BJ 8 Positive ground identification

metropolisman

Freshman Member
Offline
Hi jeff here I just purchased a 66 and I believe it has a positive ground. The battery terminal I defied positive is wire to the kill switch which is grounded to the body a white wire with a black strip runs to the engine compartment from the kill switch to the top of the coil and and the it splits and runs to the distributor. The negative wire runs to the box and then to the starter. The name of the box is escaping me at the moment! So if this is a positive ground , how do I switch it over ? I appreciate your input in advance. Many thanks to my old friend roger for spending his evening last night helping me sort out some bits on the car!
 
Hi Metro - you have posted your question in the "Forum Software Questions" forum which is a forum meant to ask questions about navigating the forum. I am moving your post to our "Austin Healey" forum where other Austin Healey owners will see it. If you're reading this you are IN the Austin Healey forum. I'll leave a "redirect" in the Forum Software Questions forum so if people click it it will take them to this post in the Austin Healey forum.

Basil
 
Last edited by a moderator:
Hi jeff here I just purchased a 66 and I believe it has a positive ground. The battery terminal I defied positive is wire to the kill switch which is grounded to the body a white wire with a black strip runs to the engine compartment from the kill switch to the top of the coil and and the it splits and runs to the distributor. The negative wire runs to the box and then to the starter. The name of the box is escaping me at the moment! So if this is a positive ground , how do I switch it over ? I appreciate your input in advance. Many thanks to my old friend roger for spending his evening last night helping me sort out some bits on the car!

Jeff, you have described a positive ground car. You can change to negative ground by turning the battery 180 degrees and reconnecting the battery cables. But, you also have to "polarize" the generator. The fuel pump has to be able to run on negative ground, and if you want the tachometer to work you have to do some simple rewiring internal and external to the tachometer. I can send you the procedure for that.
The "box" is the starter relay (some call it the starter solenoid).
 
Thanks Steve,
after some more research some people suggest swithing the wires to the coil around , the previous owner had painted the coil so there are no markings on it. I’m thinking about swapping the coil out and throwing this one in a box. Any suggestions for a new one ? I’m also going to swap my points out to Petronix and change the spark plug wires to braided .
I have solved the mystery about the single lense turn signals. The car had the front apron replaced , must have been in an accident. I’ll need to figure out how to fix that. Are you the gentleman I register my car with? Thanks again for everyones input. - best , Jeff
 
Thanks Steve,
after some more research some people suggest swithing the wires to the coil around , the previous owner had painted the coil so there are no markings on it. I’m thinking about swapping the coil out and throwing this one in a box. Any suggestions for a new one ? how to fix that. Are you the gentleman I register my car with? Thanks again for everyones input. - best , Jeff

Yes, Jeff, you need to reverse the wiring connections at the coil. Forgot that little detail, sorry. If you look closely at the coil terminals, you should see a '+' above one terminal and '-' above the other. Or, if you have an older coil it could be "CB" and "SW". CB means contact breaker, and that is the white/black wire that goes to the distributor (it's the + side for positive ground). SW is the ignition SWitch terminal with the white wire (for positive ground). To convert to negative ground, simply switch each wire to the other terminal along with the other steps I mentioned before.

I have a "Lucas" coil from Moss Motors on my BJ8, but I recently bought a spare at NAPA while on the road. It's NAPA Proformer, P/N IC14SB. Haven't used it yet. Moss also has a Pertronix coil for twice the price (www.mossmotors.com). The coil should be for use "without an external resistance".

Yes, I am the BJ8 Registrar. I have your car in the registry from having seen it on bringatrailer, but there are some additional details I would like to document. You can go the BJ8 Registry button at the top of the A-H forum home page to see what is desired. And thanks!
 
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