Wifes 2000 blazer...has problems..

Come home shut it off, later on no start just click. went over all connection cleaned retightened. battery started stinking and i unhooked it. checked battery voltage 12.3 without the cables hooked up. hook up the neg cable fine, hook up positive cable voltage drop instantly to 9.6v

Unhook the cable take out battery still 9.6, two days later still unhooked it reads 12.3...put it back in hook up cables samething happens...it drops to 10.3..left it hooked up not thinking for 2 hours. i then unhooked it and it has stayed at 10.3 for a few days..took it today and had tested and they said it was just deeply discharged, but to slow charge and it will be fine. to me the battery sounds screwy, but I'm slow charging it anyways. now i am wondering could the starter be internally shorted?? i took it off this evening and the the copper post was black like a burnt penny would look. and when you tip the starter from end to end something inside sounds like it is flopping. and Im not expert on starter internal wiring but i started testing continuity of the posts on it and when you check the post with the large copper strand going inside the starter, it is showing continuity with the starter case,an also the small stud on the solenoid.

Thanks in advance for all help..

 

It sounds to me like you have a dead cell in the battery.

 

I agree. It is also possible that you have a corrosion problem behind the positive post which is some what common, especially if it is an AC Delco battery. Been there, done that!

 

But he still shouldn't have continuity between the positive terminal and starter case, should he?

Or both terminals and the starter case, as there appears to be more than one...

 

All electric DC motors have continuity through them. If he were to say that from the large terminal on the solenoid to the starter case, then I would say that the solenoid is bad. The solenoid doesn't complete the circuit to the starter until the trigger wire is energized, at which time the solenoid kicks out the bendix and closes the contacts between the main positive battery terminal and the starter motor. But he stated that he was checking continuity between where the copper strap, the positive lead between the starter motor and the output side of the solenoid, and the starter case, not on the positive lead into the solenoid.

 

Ahhh yes, my bad...

My dads old '93 Suburban had the battery post fall out...
So did my cousins '06 Durango, lol.

My '85 S10 had the factory battery in it when I bought it in November '05

Try another battery, from another vehicle... It'll give you a clear indication if it's the battery, or a wiring issue...

 

Just replaced a starter on a '94 Sonoma that had a short in it. When we turned the key on you could hear the power go thru the relays, under the hood, and under the dash the starter wire would actually jump when you tried to turn it over, and......it was hotter than hades. The loop was backfeeding thru the ignition wires.