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| | | | Joined: Jun 2007 Posts: 48 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2007 Posts: 48 | Hi Guys! Did a search but I'm apparently a very poor searcher, or I'm not finding what I need (though I'm sure it's been covered before here somewhere).
1951 3100 w/ 216. My brother and I stripped the electrical down and converted to 12V using a Ron Francis 'retro' loom kit. We also used a 1 wire alternator which we hooked directly to the battery. This was about 3 years ago and if the truck isn't driven every few days, the battery has been drawn down to completely dead.
I can put a charger on it and it'll charge. Once started, I put a meter on the battery and it is charging. I installed a Priority Start device recently, but it doesn't leave me with enough juice to crank the truck over.
I'm at my wit's end. How do I find out exactly what is drawing down the battery so fast so I can fix it once and for all. It's not enjoyable to want to drive the truck and then have it not start most of the time.
Any help would be appreciated...
Thanks, Chris
P.S. Last week I disconnected the radio thinking that maybe the memory is drawing it down. Nope, that's not it... | | | | | Joined: Jan 2000 Posts: 591 'Bolter | | 'Bolter Joined: Jan 2000 Posts: 591 | One method that works is to:
1. Turn off the ignition
2. Disconnect the battery positive side terminal lead
3. Wire or alligator clip a 12v bulb between (in series with) the positive terminal of the battery and the now disconnected positive terminal lead.
4. If there is any light indicated by the bulb, you know something is drawing current. You probably should disconnect the radio memory to start out. That will draw some power, but it should be very little.
5. Start disconnecting things one-by-one until the bulb goes out | | | | | Joined: Nov 2007 Posts: 190 Shop Shark | | Shop Shark Joined: Nov 2007 Posts: 190 | If you used a Delco one wire alternator there is a little item inside called a "diode trio". My guess is either the diode trio is bad or you have a bad diode in the rectifier bridge. Either one will allow drain on the battery. Your local starter and alternator shop should be able to check it out and it should be a quick fix. | | | | | Joined: Jan 2008 Posts: 159 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 159 | you sure you have a good battery
1938 Gmc 1/2 ton
| | | | | Joined: Jun 2007 Posts: 48 Wrench Fetcher | | Wrench Fetcher Joined: Jun 2007 Posts: 48 | Yep, good battery...
I'll try the bulb test (I'm assuming I can use my test light) this weekend and let you know what I find. I can't remember which one wire alt I bought and from whom, but I'll yank that bad boy too and have it checked...
Thanks guys,
Chris | | |
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