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Converted to Negative Ground - Battery charging?

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BrandonBJ8

Jedi Trainee
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I just finished the conversion to negative ground. The car seems to be running fine with it. The tach is working which is the part I was worried about most. There are two problems though:

1. I don't think the generator is charging the battery. I tested to battery with a multi-meter and got a reading of 12.05 with the engine running. I revved it up quite a bit and the reading did not change at all.

2. Small, but may be related. The red ignition light comes on when I turn the car on, but does not go off when I get above 1000rpms. It does turn off when I turn the car off though.

Any help or advice would be appreciated.

Thanks!
-Brandon
 
oops, it seems very dangerous to me. I believe you are discharging your battery completely. It happened to me when I reversed the polarity of my bj8


this happens for incorrect conections on the tachometer. It discharges thru the red light
 
i remember there are two small spades that connect the bulb holder with the tachometer chassis. I think they have to be removed to avoid the short circuit
 
Jose_Miguel_Mahave said:
I would discconect the tachometer while you discover what is going on
Click to expand...


Hold on there the Lot of you! Brandon!, do not start the car again until you have polarised the generator. The generator is polarised for the previous ground configuration and must be redone as part of this conversion. Be back in just abit---Keoke
 
Hi Brandon,
Did you polarize the generator? Go HERE and look at #2 to see how to do it if you haven’t. I’d browse the entire tech article to see if anything was missed. The tach light normally has the same polarity to both sides of the light bulb, one lead from hot battery, the other from the generator. The light comes on at low RPM (or engine off) because it is reading the difference in voltage. Once the RPMs go up and the generator is charging, the voltages become the same (-12 originally) and the light goes out.
 
T0 Repolarise the generator. Remove both leads from it. Connect a jumper lead from a +12Volt source under the bonnet and momentarily strike it to the small insulated terminal on the generator marked "F" for Field. Reconnect the generator leads and you can now start the engine and you may be good to go. Somtimes reversing the polarity causes the contacts inside the RB340 Controller -Voltage regulator- to burn. But lets see how you get on.--Fwiw--Keoke
 
I polarized it earlier using that exact link above. However, I did not disconnect both leads. Could that be the problem? I just disconnected the smaller terminal and used a live wire from the "B" terminal of the voltage regulator to polarize it (sparked a few times).

Thanks!
-Brandon
 
No,just so the field is reversed. Does it charge now??--Keoke
 
Re: Converted to Negative Ground - Battery chargin

Keoke said:
No,just so the field is reversed. Does it charge now??--Keoke
Click to expand...

In my previous post I meant that when I did the entire conversion I used that link and am still having the problems. I haven't changed or done anything different since then. Is there something else I can try?

Thanks!
-Brandon
 
Re: Converted to Negative Ground - Battery chargin

Brandon,

You might try to flash the field again.

The indications that you have are that the generator is not putting out anything so assuming that everything else is OK, try flashing it again. You will see a " healthy " spark when you do this. If you did see a fairly noticeable spark when you first flashed it, it may just need to be done again. Give it a try. But when you test it, it should put out 13.5 to 15 volts if it is charging and the red light will go out after it gets above 500- 800 RPMs. If not, turn it off in case something is wrong inside the voltage regulator or the tach is shorting the output from the genrator.

Ed
 
Re: Converted to Negative Ground - Battery chargin

When I converted mine, I got so wrapped up with the tach changes that I almost forgot to swap the polarity of the ground at the battery.
Double check all of the steps that you did if reflashing doesn't help.
 
Re: Converted to Negative Ground - Battery chargin

BrandonBJ8 said:
Keoke said:
No,just so the field is reversed. Does it charge now??--Keoke
Click to expand...

In my previous post I meant that when I did the entire conversion I used that link and am still having the problems. I haven't changed or done anything different since then. Is there something else I can try?

Thanks!
-Brandon
Click to expand...
Well we better take a look at the voltage regulator. Shut Battery power down on the car. Remove the voltage regulator cover where you will see a very hefty set of points Located on the RH outboard side of the regulator . Using a fine grained non shedding sand paper clean these points and see if charging is restored.---Keoke
 
Re: Converted to Negative Ground - Battery chargin

If you didn't flash the field correctly, the RH contact may be severely burned or missing.
D
 
Re: Converted to Negative Ground - Battery chargin

Okay, now don't get too mad...but I forgot to reconnect the generator after I finished!!! I went back to go a reflash it and saw that it wasn't even connected!

Now the light goes off after about 500rpms and the battery is charging when I rev the engine. It looks like everything is successfully converted and working!

Thanks to all for your help!
 
Re: Converted to Negative Ground - Battery chargin

BrandonBJ8 said:
Okay, now don't get too mad...but I forgot to reconnect the generator after I finished!!! I went back to go a reflash it and saw that it wasn't even connected!

Now the light goes off after about 500rpms and the battery is charging when I rev the engine. It looks like everything is successfully converted and working!

Thanks to all for your help!
Click to expand...



-------12345678910^?/>,"":&*&**(*&^&*(*&6)__++!@#@!@--Keoke- /bcforum/images/%%GRAEMLIN_URL%%/lol.gif

<span style='font-size: 20pt'> </span> Finese
 
Re: Converted to Negative Ground - Battery chargin

That's ok. Now we've all got lots of troubleshooting advice when it happens to someone else.
 
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