I am new to the form and need big time help!!! My 1989 S10 blazer is eating alternators and I am now on my 7th one in 10 days. Here is what I have done so far. I have had the battery checked and recharged at oreilly's auto parts,XS power D3100 battery. I have replaced the starter,ecm,icm,ignition, Cap and rotor,plug wires. I have checked all grounds and tore apart the wire harness to check for a short in the sensing wire and the fielding wire and the two 10ga wires coming off the alternator post. I have the big 3 set up using 2ga wire. This all started when I put a new alternator in my S10. The one that was in before was there for 3 and a half years. My next step is to completely re-wire the whole alternator set up. I have gone to two orielly auto parts store's and an auto zone for the alternators. What could I be possibly missing? Could the battery be bad even though it tested good? The battery is only three months old. I still need to do a parasitic drain test because the battery went dead sitting for four days. I think I have a gremlin and would like to kill the little S.O.B. Any thoughts would be greatly appreciated.

 

When you say "eating" alternators, what do you mean? Are the parts stores testing them when you bring them back? Or, are they just not keeping the battery charged? How long have you had that battery? Did you ever drop it, or did it get banged around? From what I understand it is possible for a battery to be bad internally that tests out well. But don't hold me to that.

Just prior to changing out the first alternator (the one you had for 3 12/ years), did you do any work at all on your truck? If the battery is good, it strikes me that there is a short somewhere. If you haven't already done it, trace your battery cables all the way. Looking for looseness at any connections or worn off sheathing.