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Battery Ground Question

Venanzi85

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just recently replaced alternator in truck thinking it would solve my battery dying on me on my 77 k5 blazer, i recently put in a battery disconnect so it would not kill my battery, anyways after a few days of installing alternator battery is dead now. my question is I noticed the negative battery terminal cable to grounded to the frame, should I ground to the engine block of my 350 sbc maybe that would solve this issue?
 
Is the frame connection clean? I had to grind off a spot to bare metal for my secondary battery that's to the frame just behind/below the passenger seat.
 
I may just have to do that and maybe where my problem is just looked again its on the frame but does not look clean to me
 
I may just have to do that and maybe where my problem is just looked again its on the frame but does not look clean to me
If the battery is draining in 2 days, it’s not because of a bad ground. You have something turned on that doesn’t lose power when the key is removed (or your battery is at the end of its life).
 
I can confirm the battery is new, I always checked to make sure nothing is turned on after I am done with it, i am just trying to find whats draining the battery
 
You have a drain on the battery somewhere. Ground should not be the issue but it will cause other problems. The battery, engine block and body should all be grounded to the frame. This allows all systems to ground back to the battery no matter what they are grounded to. A braided ground strap is typical but short ground cables work too.
 
You have a drain on the battery somewhere. Ground should not be the issue but it will cause other problems. The battery, engine block and body should all be grounded to the frame. This allows all systems to ground back to the battery no matter what they are grounded to. A braided ground strap is typical but short ground cables work too.
Thank you I will reject all my ground points
 
Disconnect your ground cable at battery. Put a test light on negative post and the other side to the ground cable. If lights brightly you have a draw. If it doesn't light open the door, or turn something on, it should light brightly. Proving you have a good test light and connected well.

So if you have a lit test light, with doors closed and everything off, disconnect the fat red wire from alternator. If light goes out your alt is causing the draw. The radio memory circuit should show a dim light, you will want to pull that fuse or disconnect the radio memory circuit.
 
I just got done chasing electrical gremlins in the Jimmy so I will give you a rundown of what I found and what I did.

I drive 5 miles to work and maybe 9 miles on the way home if I go through town. I have dual batteries, no disconnect, grounds from each battery to the upper radiator support and the block. Battery cable to the alternator is #2 and wire to the starter is #1/0. Gear reduction starter and at the time a brand new stock alternator. Pioneer stereo that may have had a slight draw but couldn't find any other draw by pulling fuses. Alternator was putting out 13 to 14 volts to the original gauge in the dash. I would frequently have problems getting the engine started. Slow starts, longer than normal cranking times, etc. After a weekend of not driving, sometimes I couldnt get it started without a jump start. Kept checking allkinds of stuff and then I ran across someone on this list saying how well they liked their Powermaster alternator. So I started looking at new high amp alternators and Powermaster was the only one who would actually give info on what their alternators put out and at what RPM. I figured 100 amps at idle was good enough for me so I spent the bucks and got one. Charged both batteries separated before I installed the alternator and I haven't had a problem one since. Not one.

After upgrading all my cables, my problem ended up being not driving long enough to get the batteries charged up enough. 102 amps at idle is a whole lot better than 63 at some unknown RPM (probably top end RPM).
 
This is true short commutes are hard on batteries. I have a small electric cooler 12v. If I leave on in truck for overnight and 1/2 a day, it is approximately 50 mile at highway speeds before the aux batt is charged equal to main batt, with 105 amp alt.
 
I chased a draw in my Suburban for a long time. It started fine when just parked, but after a couple of weeks it could barely crank. The draws I saw always seemed reasonable given the pile of electronics from the factory, so I assumed some module was turning itself on while parked. For a while I got by disconnecting the battery. This summer I swapped the starter and the problem seemed to go away. The old starter was a small one of questionable history and the replacement was the beautiful Denso BBC gear reduction starter.

Anecdotes are interesting, but nobody is suggesting the parts cannon. Be a man of science, as described in posts above.
 

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