Battery Drain.....sbc

[jkl72-40]

Howdy
My battery is draining, My alt is charging great.....
its wired like this How to install a GM Alternator in a Land Cruiser...

does it need a diode?? Then where do I put it
no popping fuses
any clues?

71fj55 sbc

 

[Downey]

The problem with your link is it only tells you how to wire the older 10-SI alternator, and you may have the newer CS-130, or even newer yet. Generally when you wire one of the newer alternators incorrectly, you don't merely have a matter of not charging the battery, but you've generally burnt out the gosh darn alternator. Once you determine which alternator you have, PM me for instructions!!!!!

 

[Fuzzy Logic]

Attach a test light between the negative battery cable end and the negative battery terminal. The test light should illuminate dimly or not at all. If the test light is on brightly there is a strong electrical draw in the system. To locate this electrical draw start removing fuses one at a time. When the test light goes out the circuit in question has been located.

 

[Josie'sLandCruiser]

Hi All:

Like "Downey" alluded to, are you sure that your alternator is
actually charging?

I have been spending the last few months trying to figure-out how to correctly wire a Delco CS-130 alternator to work with a low-revving engine (2F.)

Not being knowledgeable in the electrical world this has been quite the learning experience!

Also, the truck may have a low-amp draw; consider disconnecting the battery or using one of these:

Battery Tender Plus Battery Tender 021-0128 $39.90

Good luck!

Alan

 

[jkl72-40]

yes its charging if it sits for 3-4 days it wont start but I drive it a for 30 seconds it will start right up. it gets 14 volts at the battery

 

[ranger]

Might have a bad cell or two in the battery. Have you hooked up a battery load tester up to the battery when its fully charged?
If you don't have that tool, you can take it to Schmucks or Vatozone and they can do it.

 

[Plowboy]

Check to see if your drain is at the starter. chev solinoid are known to allow a drain at the starter motor. Test at the connection on the bottom, not the connection from the battery. If there is a draw there, replace the solinoid.

 

[2damslow]

You need GM alternator part number GM7127
It's the one with the built in diode.

 

[jkl72-40]

Got it. gm7127
I will check the started next
thanks

 

[croozy]

yes its charging if it sits for 3-4 days it wont start but I drive it a for 30 seconds it will start right up. it gets 14 volts at the battery

mate I have exactly the same problem. I have changed alternators, made sure that it is charging properly, load tested the battery. I have checked for a drain & it has a .001 milliamp drain which is put down to the memory for the stereo & ECU but if the car sits for 3 or 4 days the battery will be flat. I'm still scratching my head.

 

[jkl72-40]

???

Checked the starter s-noid nothing there
But now my hazards work they did not work before
Could it be the key?
My rear window will go up but not down without the key on
Out of my six fuses 3 dont have power and 3 do.= normal

 

[Brian in Oregon]

I found a major drain in my FJ40. The PO has a huge stereo amp in it, and the ginormous power cables running to the rear were under the carpet, with the bare frayed ends resting on the floor. The paint prevented a direct short, but it was enough to drain the battery in a couple of days.

However, the battery will still go dead after 5 to 7 days of sitting. Try as I might I could not find the slow drain. Threw in the towel and installed a $5 kill switch on the battery terminal. No problems since.

I have a Chevy alternator on my SBC, but it never occurred to me to see what kind it is. I assumed it was a "one wire".