Tweet
I have twin Yamaha 1998 250 HP EFI motors (OX66). My starboard motor is connected to a single battery. My port motor is connected to 2 batteries and handles the power to the main panel, gauges, and electronics. Both motors and the 3 batteries are tied together through a Guest Isolator (70 amp I believe).
This season I found my port batteries were not holding a charge, so I replaced all of the batteries - did not help. I had my mechanic confirm the port motor is charging (did not check the starboard) and it is. I disconnected the Isolator and ran a diode check - it's working.
Here's what I found confusing...when I checked the current of the auxiliary wires (while disconnected from the isolator), I had 2 completely different readings from each motor and they did different things while I increased the RPM's. The starboard motor started at 14v and dropped to 7v after about 1 minute at idle, then when I increased the RPMs, it dropped to 7v. The port motor does the exact opposite. It started at less than 2v and increased to 5v when I reved it.
My initial thought was the I had a break in the port motor auxiliary line causing the low volt reading, but the drop on the starboard when I'm increasing RPMs has got me confused.
Final note...I did extensive rewiring when I purchaced this boat 4 yeras ago and the port batteries have never held as high a charge as the starboard batteries.
ANY SUGGESTIONS?????
This season I found my port batteries were not holding a charge, so I replaced all of the batteries - did not help. I had my mechanic confirm the port motor is charging (did not check the starboard) and it is. I disconnected the Isolator and ran a diode check - it's working.
Here's what I found confusing...when I checked the current of the auxiliary wires (while disconnected from the isolator), I had 2 completely different readings from each motor and they did different things while I increased the RPM's. The starboard motor started at 14v and dropped to 7v after about 1 minute at idle, then when I increased the RPMs, it dropped to 7v. The port motor does the exact opposite. It started at less than 2v and increased to 5v when I reved it.
My initial thought was the I had a break in the port motor auxiliary line causing the low volt reading, but the drop on the starboard when I'm increasing RPMs has got me confused.
Final note...I did extensive rewiring when I purchaced this boat 4 yeras ago and the port batteries have never held as high a charge as the starboard batteries.
ANY SUGGESTIONS?????
Comment