[bruce537]

HelloI have a 1998 225 Yamaha. I troll a lot at idle speed, when the motor is running at trolling speed, the voltage on the meter on dash continues to go down like to 11.8 v. Then when i bring the RPM's back up and run to the next spot the voltage meter goes back up to 13.8 to 14.2 v. This happens no matter which battery I run on. I do have a separate terminal block for all accesories and that goes to one batteryEven though I have the battery switch on one battery ( not both ) doesn't Yamaha still charge both batteries?Thanx Capt Crunch

[rodbolt]

hello that depends on who rigged it. the engine is equiped with a seperate cable that will charge a second battery without a seperate isolator. however I cant see you rig and odds are very good that the 6 dollar an hour monkey that rigged it hasnt a clue either. you need to use an analog meter at the fuse assy under the hood. if you get 14 volts there but not at the battery then look for a bad battery cable or switch or connection. post back what type of boat and who rigged it and where. here the past 3 weeks I have spent over 30 hours trying to straighten up factory rigging problems from a few dealers in the wilmington area and the southcarolina area. as well as some factory pro-kat screw ups but those we are used to. post me back a model number and Ill try to help.but if its a rigging error it will be hard to describe. post back what gauges and what brand of gauges you have. good luck and keep posting