Have a 2000 tracker 125hp motor. Never have had a problem out of it. Recently when i am out and have been running my graphs and livewell all day when i go to start the motor it hesitates for a min or so. I always charge the cranking battery when i get in along with the trolling motor battery. When i was out i went into diagnostic view and while giving it pretty good amount of throttle the voltage was fluctuating from 12 volts up to 16 volts. Is this right or should it be constant? The battery is about two years old. Trying to figure if i have a bad cellor if the motor isnt charging correctly. Any ideas?

Charging voltage will vary with rpms normally. If voltage is varying at say 4000rpm it is a sign of regulator or stator going out. I would check water level in the battery and have it load tested.

Took it out today and it jumped from 12 to 16 volts back and forth no matter if i was turning 2000rpm or 4000rpm. I am leaning toward the voltage regulator. A while back i had a problem with my tach jumping around and not reading right. I looked at it and a couple of the wires looked like they had gotten hot and were stuck together. I messed with them and after that the tach seemed to be fine. Im thinking it might be time to just get a new voltage regulator. I will also check the water level in the battery and have it load tested.

It does sound like a reg. problem. You should not be charging over 14 - 14.5 volts.

I have a 2001 Yamaha 200 hp and was having the same issues. I found a loose ground connection on the back of the tach that was affecting the gauges. I would put a tester on the battery and check the voltage there while running, to see if you get the same readings.

When i was having tach problems i checked all the wires on the guage and when i messed with the voltage regulator it fixed it. I went ahead and ordered a new one online. Found it for 65 bucks. Will post if it fixes the problem.