Low voltage partially solved & sync gauge now more accurate

I had another mystery with the boat last week. I decided to equalize my batteries, I did it last year before I added 2 additional batteries and it worked fine, Pronautic 1250 (3 bank, 50AMP Charger). This time when I set the charger to equalize I did not know I was going to have problems. I should have turned off the batt switches (I know now) in any case after equalization, I went to start to motors and the starboard side had no power. I hit the parallel switch and all was fine, or so i thought. We left the dock and went about 15 miles to fish. When we were ready to return, the motors started up with no problem. On the way back at a slow speed due to the no wake zones, the starboard engine died. It would not restart, and the parallel switch did nothing. So I continued home with only one engine.

The next day I started tracing the wires from the ignition switch and when I got to the first harness connector, one connector looked burned, not black but brown as if from age. I disconnected the connector and it appeared to be rusty, not burned. This was for a primary wire, so I cut the wires and did a direct connection. Everything was working again without any problems. The funny thing is I no longer had the severe voltage drop, minor now when running the blowers. Today we were out all day and I found no problems with the engine electrical. It is normal to be waiting for the problem to reoccur.

Since I had the dash panel open, I checked and cleaned all the other harness connectors. Now my snyc gauge is working far better than ever. The one question is when the engines are off, it is not always centered at "0". I wonder if this effects the readings?

So, Now I can begin the new year with a new set of minor boat issues, more on those later...

Happy New Year to all and it should be a great year.

Sounds like you are on the right track. And happy new year right back at you!

Nice feeling when you find something that has been irritating you for a long time, isn't it ? Glad you got it. Hope your New Year is great !....Lee

The one question is when the engines are off, it is not always centered at "0". I wonder if this effects the readings?

Just prior to starting the engines, when you turn the ignition key on...does it centre on "zero"??

I have replaced my analogue tachs with a dual digital tach which allows for more accurate sync but prior to that when I shut down the engines one tach or the other did not make it to "zero" when the power was withdrawn. I did notice as soon as I turned on the key(s), prior to engine start, the tach went to "zero". That doesn't happen with the digital tach.

Don's observations are keen. It's the powered on position of the gauge (with no input signals) that will show its state. Even though it zeroes in that condition doesn't ensure the meter or its driving electronics are error free. Best way to test both is remove them and bring them to the test bench. If that's not an option, one easy check for the whole system is to remove one tach input (P) and just jump the other tach input(S) to the (P) bare terminal with the engine running, the gauge should sit on zero all the time.