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So my battery made me buy a starter I think. It showed 12.6V then sometimes 15V. Seemed odd but I blew it off. So new starter drags also. I only have a multitester. i know a battery can take 250 AMPs and up when starting motor. I can't measure that under load. I did watch the voltage and it went tp 6.3V. But I don't know what voltage does during start. Never had to do that. Has someone seen or know what the voltage does?? The good old FLAPS guy didn't know how to test for sure or if his tester will give a load to battery. He said charge the battery and come back. No thanks. So I write tonight hoping to get help.

Load the battery to 1/2 the cold cranking amp specification for 20 seconds, or find someone who can. With the load still applied, the terminal voltage should not drop below 9.5 volts. A good battery should crank the engine with the ignition disabled for 30 seconds without the terminal voltage dropping below 9.5 on a 12 volt battery, or 4.5V on a 6 volt. That's been the industry standard for over 50 years.
Jerry

I don't know how to load it. It drops to 6.3V right away.............on a 4 cylinder motor!!!!!!!!!!! I just want to be sure I'm not doing something wrong or motor is locked, which it's not. I want to be sure it's not the remote relay. The old starter kept gradually dragging and I kept charging battery, thinking starter. I "rebuilt" it. I think it was the battery all along. I can get a free new one at Costco but I gotta know if it breaks down to feel better. I guess if I get a new one that will tell me. Going to try and find a person who knows how to use a load tester tomorrow.
I should have known it was the battery, I am losing my common sense. The darn thing kept charging up good. My battery charger has NEVER overcharged a battery to 15V. I have NEVER heard of a bad battery showing 15V and then 12.6 within minutes between testing. So I blew off this info. But now the fight is on.

Like you said the internet says 9.6V min during starting. I just didn't know if that is reliable the way I did it.

You have a "sulfated" battery- - - -one where the normal chemical process of charging and discharging has been interrupted by the formation of lead sulfate crystals that reduce the current capacity without affecting the open circuit voltage. Loaded voltage will drop dramatically. I taught battery theory and servicing for 30+ years. There's a way to break down sulfation, by completely discharging the battery and S L O W L Y recharging it repeatedly, (10 amps or less) but it takes weeks and numerous cycles to work. Very few people have the time or patience to do that.
Jerry

Bartamos, use a known good battery from one of your other vehicles as a test to see if the starter is at fault.

Like HRL says "Load the battery to 1/2 the cold cranking amp specification for 20 seconds, or find someone who can".
I've always used a general rule of thumb that battery needs at least 1 CCA per cubic inch of motor.
If you feel like an investment, or if a local shop cannot load it for you, most Farm and Ranch stores, or an O'rielly's can sell you one of these:

https://www.schumacherelectric.com/products/battery-load-tester/

That tester is a "P.T. Barnum special"- - - -it's made to sell batteries, not test them. To load a battery properly, a tester must have a carbon pile variable resistor, and an ammeter to monitor how much load is being applied. The one in the ad is a "ones size fits none" that applies a fixed current load without any regard to what a specific CCA rated battery needs for a proper test.

Here's a real battery load tester:

www.ebay.com/itm/293816270395?

Jerry

Battery was bad. Thank you everybody for your help. I learned from you. belive it or not, the 15V was a bad multimeter. Should have used my Fluke.

Words to live by!

Remember the old ad- - - - - -"If it works, it's a fluke!"
Jerry

bartamos An old guy once sold me a power pyle made into a 32 volt WW 2 generator /regulator testor. I learned with that outfit !! Later then got so I could afford Sun equipment,my current carbon pyle (Sun) will make any battery sweat . Take it to the woods junk yard when buying used batteries. The WW2 outfit is still working,and you can fix it if you hurt a component. May have to qualify that "fix" if you can find the component !! I have some of them on my shelf from the olden days of alternator "school".