It cranks sluggishly. It actually starts ok because it's firing up on what may be the first rev but it's really slow sounding. Battery was about 30 months old. Spec. gravity thingy with the floating balls said cells were only at 75% charge. I checked system voltage with engine off and it was about 12 point something and with the engine running 13 point something to 14. Seemed better for awhile so I was been watching the vehicle's own voltmeter and it seems where it should be, near 14 with the engine running. I also removed and emery'd the posts and cable clamps.
It started to seem sluggish turning over again in the last few days so today I checked the battery cells and this time 50% to 75%. Okay, time for a new battery so I got a pro-rated warranty replacement. After putting it in I was hoping to hear a vigorous start. But nope, still sluggish with the new battery. Of course the new battery, not coming from a place that keeps them on trickle charge, isn't really fully charged so I am hoping after it really gets charged it will in fact cure the sluggish crank but is there anything else I should be looking for? Do starters get "weak" or more likely just fail flat out?
Also, is it normal to get oddly high battery voltage readings immediately after taking off charge, like in the 13's rather than 12 point something, maybe from "surface charge" or something? I'm not charging it at any great rate, just 3 or 4 amps....not much more than a trickle. SG doohicky said the cells were at 75%.