Batteries can have voltage but don't have the amperage to do anything. One of the reasons I get the daily driver batteries from Wally World. Good warranty I can access just about any where there is a Wally store that has auto.
Took the battery to a local Auto Zone, and the load test was OK..... Put the battery back in the car, no power anywhere....again. Wiggled the negative cable and there was power, and one click from the starter. I cannot seem to see where the negative battery cable connects. Does anyone know for a 72 GS? Looks like it goes under the A/C compressor.
Stupid question: Did you clean the terminals? Like really clean them on both the cables and the battery posts? They can look clean, but get a coating on them that will inhibit a good connection.
Cannot get to the negative end to the block easily - looks like a lot of disassembly. That is nest on the list.
ie - a jumper cable from neg battery post to alt housing - pull neg battery cable off battery post first.
There are no posts on the battery. It is a side terminal version. I plan on a jumper cable from battery negative to alt housing next to see. It is really a strange situation that I have not encountered in 40 years of wrenching n these GM cars.
Without doing proper voltage drop testing, anything is just a guess. But you still should be able to fix this. Turn the headlights on, and if they don’t come on or they come on dimly, wiggle both of your connectors at the battery one at a time, noting any change in the headlights. Do the same for the ground cable on the alternator bracket or wherever it goes to on the block, and carefully do the same for the positive cable on the starter.
Hi Paul,sorry for the problems you are having.Changing the ground cable should not be a problem,it just looks hard.Its only one bolt under the alternator,with a 9/16 short socket and with the 3 inch extension,you should be able to take it out in a few minutes.I'm 83 years old,I can do it ,no problem.Also,as it was suggested,cleaning of both negative and positive cables is a must,and I would also recharge the battery, they tested and its good,but as is maybe does not have enough juice to start the car.Bruno.
UPDATE - Fixed it! Finally got a warm day to work on the GS for the no start condition. Thanks to all who gave great tips on troubleshooting. It ended up being the ground cable connection to the block. The connection was made with a grade 1 bolt and flat washer - no locking washer of any type. It had vibrated loose, and the cheap hardware was rusty. Cleaned it up, and put in the proper hardware. Starts like a champ now. While I was under the car, I installed a new NAPA starter, non a reman. Wasn't too bad.
I had a similarly annoying problem last year in my drag Regal. I keep a Battery Buddy on it in the trailer most of the time. Was at the track when it happened. Took off all of the straps holding it in the trailer, turned on the master battery switch, climbed in and tried to start it. Fuel pump was humming just fine but as soon as I hit the starter button...."Click" then nothing. Checked the battery for voltage and it was fine. Pulled the positive cable off and everything looked clean and dry. But upon a closer inspection I found some gray dust in one Quarter sized spot on the positive post. Cleaned it off with some Emory cloth and it was as good as New!! I guess there was just a little too much clearance between the post and the cable end and the charger was just shorting instead of charging. Put a little battery grease on it and it's been great ever since. Simple fix but left me scratching my head because everything looked clean and tight! Guess you just never know what little problem can rear it's ugly head!
