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Pos-to-Neg Ground Conversion

673000

Freshman Member
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I just converted my BJ8 to a negative ground. In doing so I have to convert my electonic tach to a negative ground. Does anybody know what company to send it to to get the conversion done? and at what cost? Thanks for a response.
 
You could contact Nisonger about this. I'm sure they deal with it a lot. Their web site is:
https://www.nisonger.com/

There are also several web sites that discuss the conversion if you wish to try this yourself.
 
it is really simple to do it yourself. Just requires a soldering in one of the components. If you have ever done a soldering of electronics you can do it by yourself. If you wish I can tell you hoow to do it
 
What is involved converting positive ground to negative ground. as I really would like to convert my 60 BT7 when the time comes?
 
673000, If you decide to do it yourself I have a tip. While you have the tach open on your workbench to make the neg ground conversion, also replace the .2 MFD capacitor. My tach was reading a little high before I made the neg ground change. After I made the change, It was indicating over 2000 RPM when at a slow idle. I searched the web and found this web site that explained the problem and how to fix it. I had to take my tach back apart and replace the capacitor mentioned in the web site, then I had to drill a hole in the case so I could adjust the pot with a plastic screwdriver. I then was able to adjust my tach indication to match the standalone tach that I hooked up to my car for a reference. https://hometown.aol.com/bgahc/01_jwha_tachreadshigh.html
The new capacitors are dirt cheap at radio shack and quite easy to replace when you already have the tach open ! One more thing, the inside of my tach case case was apparently painted white at the factory to help in lighting up the tach when the lights are turned on. They didn't do a very good job in covering the entire inside of the tach case with white paint. There was also some discoloration of the little remaining white paint. I cleaned the inside of the case and then sprayed some white paint all over the inside surface. Between the white paint and new bulbs, the tach is now a little easier to see in the dark with the dash lights on.
 
Hi Stinky 60, for the BT7 the fuel pump must be considered. If the pump is a points type original the suppresion Capacitor should be replaced with a non polarised 0.047 Micro Farad 600 volt one. If the pump is of a later design it will contain a diode whose leads will require reversing at their connection under the cap of the pump.If the Pump is of the new electronic solid state type it will require replacement with one applicable to the NEG ground configuration. Next the leads attached to the coil will require reversing. If the coil terminals are marked CB & SW the SW terminal will now connect to the distributor terminal while the CB terminal will go to the Ign switch. If the coil terminals are marked + & - then the - terminal will connect to the distributor and the + terminal will connect to the Ign switch. Finally you will be required to repolarise the generator and you are now Negative Grounded.---Fwiw---Keoke
 
Converted mine to neg earth, so as to be able to put immobiliser on, now all I have to do is put a caution sticker on!
 
WOT! ZBLU, is that "immobiliser" any thing like a Rim Embellisher?---Keoke /ubbthreads/images/graemlins/lol.gif
 
No Keoke, its a legal requirement over here for insurance purposes!, figure it will take todays hi-tech thieves about 2 minutes to bypass, but will they know about the low-tech off switch on the battery and/or the inertia switch manually set in the off position! /ubbthreads/images/graemlins/smile.gif
 
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