Bad Alternator?

[DSBATCHELDER]

2006 Four Winns Bow Rider with mercruiser alpha 1 135 hp Started out yesterday and while cruising on the lake noticed oil pressure guage was not reading. DisConnected sending unit reconnected, checked wiring harnesses, etc then guage started working. Then noticed at cruising speed voltage guage would drop for a split second, almost cutting the boat off then go back to normal. Did this maybe 3 times. Then as i was crusing along,all guages reading fine, a 15 a c/b next to the ignition switch would trip. Did this twice. While running the boat on a hose today, noticed that the vols guage reads 12 v with the ignition in the one position or cranked. I pulled the alternator to have it tested. This is the original unit. New to this board. Any advice would be appreciated.

 

[bruceb58]

Sounds more like you have bad connections somewhere. I would check all the cables that attach at your starter, battery and engine ground.

 

[midcarolina]

Sounds more like you have bad connections somewhere. I would check all the cables that attach at your starter, battery and engine ground.

I agree........ even if the alt. quite charging the engine would still operate normally until the ignition/accessories depleted the battery.