Alternator Draw

[jimzag]

Hi I just changed my 251 to 12 volt with a Delco one wire alt, and 12 volt coil.
Now if bomber sits for a day or two the battery is Totally dead. There isn't
anything on And there is no spark at all when you contact the cables to the posts. Anybody know what the problem could be Thank you

 

[leadarrows]

Try using a test light between the cable and the battery or between the one wire on the regulator and the regulator. If the light comes on you have draw. I have to unplug my alternator on my tractor to keep it from draining my battery's and I am still tracing down why. I hope someone else helps you that knows so I can fix mine as well.

 

[jimzag]

Ok thank you I will check that out

 

[duckscarfer]

ok quick question, do you have a amp guage wire on the the one wire alt hooked up? Im assuming so. the problem with the gm one wire alt is the can back feed power direct from the batery through the amp guage and back into the ignition system causing a draw and in some cases the motor while running can keep running when you turn the key off due to this backfeed. good news is there is a fix for it though. Speedway Motors part#910-64100 its about $18 it is really designed to be used with a stock gm alt without the one wire conversion but th ekey is the resistor that is in place between the amp guage and the alt. thats what stops the back feed. good luck. also have your batery tested it might have a bad plate in it causing it to draw itself down.

 

[benz9]

I use a kill switch that I bought at Princess Auto. Just like most military tracked vehicles, the kill switch is a straight cut-off on the positive side of the battery!

 

[benz9]

Here's what it looks like. I haven't had a problem since.

 

[jimzag]

Thank's Guy's I have installed a switch for boats that basically is like the kill switch and it works. I am still going to put on the diode That Duckscarfer suggested . jim

 

[leadarrows]

ok quick question, do you have a amp guage wire on the the one wire alt hooked up? Im assuming so. the problem with the gm one wire alt is the can back feed power direct from the batery through the amp guage and back into the ignition system causing a draw and in some cases the motor while running can keep running when you turn the key off due to this backfeed. good news is there is a fix for it though. Speedway Motors part#910-64100 its about $18 it is really designed to be used with a stock gm alt without the one wire conversion but th ekey is the resistor that is in place between the amp guage and the alt. thats what stops the back feed. good luck. also have your batery tested it might have a bad plate in it causing it to draw itself down.

This could be my issue. When I replaced the alt I used a GM one because it was a 4th of the cost of the John Deere replacement.

From that Speedway motors site:

• 91064100Overall Length
  8 ft.
  
  Sold in Quantity
  Each
  
  Notes
  Not for use with one-wire alternators.
  
  

 

[duckscarfer]

yea I think the one wire alts are a waste of money just a stock gm alt work fine if you just take the red wire from the two prog plug and jump it dirct to the main charge post. essencially the same thing the one wire alts is doing. But Ill tell you I run a main shut of switch on mine too. I learn a long time ago racing cars that a main shut off switch will save burnt wire and fires. Well worth the money...Its hard to stop a electrical fire without being able to cut the power.

 

[Snowtrac Nome]

I will agree, the 1 wire jobs are a waste also by not running your regulator wire on a switch you can burn out the regulator on shut down. it will also drain the batterys as the regulator is always powered up I always run a standard delcotron when I can and if not available than a master disconnect switch is added.