Crusader 454 has low voltage reading at 12 to 13 volts?

Question

My Bertram 30 w/ twin Crusaders 454s. Both Engines each run off of 2 4D Battery. On the Starboard side, the 4D runs all the boat DC electronics and appliances. Now Battery, even after being charged has very little juice to crank the starter.

When running, the reading of the Volts is around 12 to under 13, while the other side is reading a strong 13.5 volts.

Is this a battery problem, or is it a charging problem? Also, how do I test the Alternators output to insure she is putting out the proper charge?

A little history, I have owned the boat since 2001. I have replaced the Starboard 4D 2 times, this maybe the 3rd time. When at Anchor for hours, many time the Battery will run low to the point I need to jump with parallel switch to start the Engine. However once started, the Volts would go up to 13.5. Also, at the dock, after being charged, she starts right up. Now, there is not enough juice to start.

Is this normal for a Battery to die that runs all the Electronics / Appliances?

Answer 1

Those big blocks like voltage is it a high torque starter. Check cable ends & grounds, Battery may have a dead cell do a load test. If every thing checks out. Timing may be a little advanced.Check the belts as it may be lose or warn.adj or replace.The battery will die if not being charged from belt issues. Also check the red wire from the alt as i always increase the size to #8 wire replacing the #10 good luck doesn't sound serious.Just a boat thing.

Answer 2

I suggest you have the electrical checked. It is not charging the battery and could be a hazard for you and family and friends