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I have checked fuses, wires, everything. There is a big draw at the battery but i can't find it. Any suggestions? 351 with no AC.
 

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How long does it take for the battery to go dead? Over night? After a week? Do you have a multi-meter or a test light? Do you know how to measure to see how big the draw is?
 

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Lets see if I remember parasitic load test... If you have a multimeter to measure amps- turn key to off, all lights/accessories off. Remove negative battery cable and hook the meter in line of the battery and the cable. Wait a few minutes for the system to go to sleep. Check amp draw on multimeter (I forget how much is acceptable, but it should be very low). If there's a noticeable draw, start pulling fuses one by one until the meter shows the draw drop. That will show you which circuit is still drawing power when everything should be shut down. *Someone correct me if I'm wrong... I haven't had to do a draw test in awhile.
 

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had the same issue, it was a weak alt and faulty voltage regulator.

if you havent upgraded to a 130-200amp alt, now is the time.

Also, prob need a new battery. A failing alt. over time will work a battery to death. If you have any notable voltage loss with the ignition off replace it, around $100 at wally world.
 

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2bet, do you have a test light? If not get one. You have a draw.

Do this:

Since you have two battery's take the positive end from the battery off the starter relay. Next put the test light on the cable/wire and the other end off the relay. The light should light up dim due to power to hold radio memory/clock. If the light lights up nice and bright (like it would if put across to check the light on the battery), then you have a draw. To isolate this draw, while test light still on the two places for test above (if you got to get someone to hold it, do so), start pulling fuses one by one until the light goes out, or back to dim. Once the light dims down, you've found the circuit of the problem. Next find out whats on that circuit and start examining any potential problems. This will tell you which fuse to remove during your parking so the batteries don't go dead until you find the real source of the draw on the circuit.
GL :thumbup
 

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Another thing people miss and i have had it kill battery is the starter, if it isnt grounded right, its one of 3 things alt, starter, bad battery...seen people have bad battery cables...good point on the sylonoid i forgot about that myself
 

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yo!

good parasitic stuff Sackman!

Also, have batty tested for a Dead Cell.
Typical shade tree tests; horn hinks, internal lights work, radio ok etc; but there is a slow cranking condition, then the lights go out

"... Sometimes, a battery will have just one cell go bad or short out. When this happens, the battery will seem fully charged, but fail to start the car, or it may start the car right after charging, but then fail to start the car an hour or more later. If this happens measure the S.G. in each cell. If one cell has a lower S.G. than the rest by a significant amount, replace the battery - there is no way to fix this problem. This condition most often happens to batteries subjected to lots of vibration, and sometimes to new and almost new batteries that have a bad cell from the factory..."
Source: by Gordon at partsavers.com
 

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i hear all the time that a bad solenoid would drain the battery and its usually the last thing people check when they have this problem
x3

My Solenoid had lost a screw which properly aligned it to the wall. Then if you add any small draw to it, battery dies.

Additionally, what kind of battery do you have, i.e. how many amps? If it's 'just' a regular car battery, it might be a little bit too small for your rig.
 
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