12v conversion draining battery

homer14 · Jul 31, 2016

Hi,

I just purchased an 8n that has a 12v conversion. I'm new to this as my old one is still 6v. I noticed that the connector on the
alternator which has a resistor in it to jump two poles on the alternator has the resistor getting hot and staying hot with
ignition off too. If i pull the connector out then the battery doesnt drain so I'm guessing the resistor is draining the batter
via heat.

Anyhow, i clearly suspect the wiring and more so because there is a snipped wire in the mix (see pic). I tried ot find a diagram
online but it seems you only get one when you buy the 12v conversion kits. also, this is a 48 8n which from what ive read isnt
supposed to use the resistor so it may have been the wrong kit the prior owner installed.

I'm happy to get and upload more pics of under the hood latch or elsewhere if needed. any help appreciated.

homer14 · Jul 31, 2016

not sure why pic isnt showing.. try 2

https://s31.postimg.org/ju8wyxpcr/IMG_5891.jpg

homer14 · Jul 31, 2016

try 3 on image. trying a different web site.

https://i.imgsafe.org/e381f688eb.jpg

HFJ · Jul 31, 2016

hi homer. the problem isn't those websites with the pics, u have to enclose the link for the image with the image tage. highlite the link (be carefull not to hilite anything extra, like blank spaces) and click the Img button up above the box u type the post into. this assumes u use modern view, on classic, i don't know if ther eare buttons.

HFJ · Jul 31, 2016

image tags* not tage.

HFJ · Jul 31, 2016

HFJ · Jul 31, 2016

(quoted from post at 15:45:42 07/31/16)

lol, i stand corrected. it would appear that this site is inserting extraneous data into the image links, thereby rendering them useless.

Den N Ms · Jul 31, 2016

Homer,Here is the wiring setup that you need.Does your 8N have a front mount distributor or does it have a side mount distributor?

Bob · Jul 31, 2016

HFJ · Jul 31, 2016

ah, thanks, bob. i didn't know this forum supported HTML

petehall · Jul 31, 2016

I suspect the diode wire is on the wrong side of switch
I did that one time and alt.gets pistol hot after awhile.

JMOR · Jul 31, 2016

homer, I have seen that setup sold as a 'one-wire alternator' method. It is pretty crude. What is color code on that resistor? You can still make it work without the constant battery drain if you connect the wire going to connector to switched side of ignition switch instead of to the stud on back of alternator. How long does it take to drain the battery to point of no start?

WW2N · Jul 31, 2016

Maybe------- is this it
Untitled URL Link

Bob · Jul 31, 2016

It seems likely to me that the guillotined wires coming out of the harness were originally intended to be attached to the "G"round and "F"ield terminals on the OEM generator.

homer14 · Aug 1, 2016

Wow lots of replies, my replies are below:

[Den]
Thanks for the pic. Is your diagram for the "2-wire" method? I think i have a "1-wire" setup but im not sure. This is a front mount (1948) distributor. Does that change anything in your comments?

[Bob]
Thanks for posting my pic in a format that works. I inserted my pic url into the url box in 3 ways and no luck.

[Pete]
Does this mean i need to just remove the resistor and put it inline on the other side of the switch? i didnt see a diode in the mix anywhere but maybe i need to look closer, perhaps its under that black tape. when you say switch are you referring to my ignition switch or some switch built into the alternator?

[JMOR]
Which wire on the stud of the alternator are you proposing i move to the switched side of the ignition switch? The one that is short between the top plug connector and the stud, or the one that is long connected to the stud?

[WW2N]
Yep that link works.

homer14 · Aug 1, 2016

A couple more responses to JMOR's questions. I had to go to the barn quick.

[JMOR]
The resistor looks to be red, black, purple,yellow/brown/orange

the last color i put yellow, brown, orange on is because its sort of brownish burnt looking and i cant quite tell what the line is but its one of those. if those are significantly different in resistance and change things let me know which resistor i should go buy and put inline.

it seems to drain over several days. i havent watched it with a multimeter to see honestly but i know ive gone out and started it several days before i figured out that unplugging the resistor connector stops the drain.

JMOR · Aug 1, 2016

(quoted from post at 08:09:49 08/01/16) Wow lots of replies, my replies are below:

[Den]
Thanks for the pic. Is your diagram for the "2-wire" method? I think i have a "1-wire" setup but im not sure. This is a front mount (1948) distributor. Does that change anything in your comments?

[Bob]
Thanks for posting my pic in a format that works. I inserted my pic url into the url box in 3 ways and no luck.

[Pete]
Does this mean i need to just remove the resistor and put it inline on the other side of the switch? i didnt see a diode in the mix anywhere but maybe i need to look closer, perhaps its under that black tape. when you say switch are you referring to my ignition switch or some switch built into the alternator?

[JMOR]
Which wire on the stud of the alternator are you proposing i move to the switched side of the ignition switch? The one that is short between the top plug connector and the stud, or the one that is long connected to the stud?

[WW2N]
Yep that link works.

s I said before, "connect the wire going to connector to switched side of ignition switch instead of to the stud on back of alternator." or as you say here, "The one that is short between the top plug connector and the stud".

Charlie in NY · Aug 1, 2016

Had the same problem with my 12v converted 640; plus an occasional battery leak. I finally just pulled ALL the wiring and redid the whole thing. Ended up with about 15 feet of unused wire that prior owners had just bypassed and left hanging. Sometimes one end, sometimes both ends. The solenoid connections were plain scary.

What a difference! Well worth the afternoon and a few new crimp-on terminals investment.

homer14 · Aug 2, 2016

Thanks everyone for the help.

[JMOR]
I did as you suggested and "think" all is well now. I'll check the battery and the resistor tomorrow and see if its draining and hot.

There is no longer voltage hitting the resistor and connector unless the ignition switch is enabled thanks to your tip and there is only voltage hitting the side port on the alternator (this is normal right?)

JMOR · Aug 2, 2016

(quoted from post at 20:30:39 08/02/16) Thanks everyone for the help.

[JMOR]
I did as you suggested and "think" all is well now. I'll check the battery and the resistor tomorrow and see if its draining and hot.

There is no longer voltage hitting the resistor and connector unless the ignition switch is enabled thanks to your tip and there is only voltage hitting the side port on the alternator (this is normal right?)

es

homer14 · Aug 3, 2016

Battery was 12.35 after running, then with a multimeter connected it watched it tick down .01v each second to 12.20 or so. Then overnight it dropped to 11.95 but with a multimeter on it now it doesnt tick down (drain).

So i think its fixed and i just have a battery now that wont hold a charge! Thanks guys!

12v conversion draining battery

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