battery/ regulator issue

So i have a rzr that died on the trail due to the battery not charging (8V)… pulled every non essential fuse and let battery recoup on its ow. No luck. Ended up getting towed out of lost trails atv park. We found a loose battery connection at the trail and water looked ok in the battery. When we got back we checked all electrical connections etc. Put a spare battery in it and started right up and charging to 13.5V. But when we check DC amps it jumps 3A, 15A,7.5A etc…. my buddy and i were always under the impression that a stator and voltage regulator should be constant (or damn near). Any opinions? Not 100% sure how/ where to check the VR or stator. I am looking for the factory service manual or even a wiring diagram.

I charged my OEM battery back to 13.3V and threw it back in. After a half hr of sitting 11.8 volts, shot rpms up for 15 minutes and it stayed the same. Threw replacement back in and it charged right up to 13.6V after it sitting at 3300.