Voltage Problem -250 XS

[yellowjacket5]

2006 250 XS
220 hours

Hopefully someone can help me with a problem that the guys at my shop have not been able to diagnosis. While at idle speed and lower speed, my voltage is running where it should be (i.e., 14.1). However, as soon as I accelerate the voltage begins to drop. Yes, the trim is being used, however, once I am off the trim the voltage does not climb back to 14. As soon as I hit mid-range speed the voltage has dropped into the upper 11 range and guess what...Smartcraft does it job and and gives me the low battery warning and will eventually go into Guardian if I do not back off. As soon as I back off and get back to the lower end the voltage climbs back to 14. This problem started last summer during a tournament but diasappeared during the day. Everything was fine until a couple months later when it popped-up again. Two different batteries have been tested and all electronic connections have been removed. Yet the problem now persists every time I run the motor. Any help would be greatly appreciated. Oh, I almost forgot. The guys at the shop have run the various tests and nothing is showing up on the computer.

[EuropeanAM]

Welcome to BBC!

Problems like this can be a real "hoot" to locate!

Outisde of the battery and it's connections, Common causes I've seen:

-Loose ground lead (or poor connections to the ground lead) at the alternator
-Loose battery ground cable lead AT THE ENGINE BLOCK (below the starter)
-Loose PRIMARY output cable connection (or faulty fuse-link cable)
-Improperly installed belt tensioner (supplying inadequate spring tension)
-Failing alternator (especially if the brushes are hanging in the alternator and making poor contact).

[yellowjacket5]

Thanks for the welcome and thanks for the information. A real hoot....I hear you.