Electrical problems with new boat / Yamaha F50 motor

[MikeMaine]

hey everyone,

my family just bought a new PolarKraft boat that has a 2008 Yamaha F50 motor.

It has had electrical issues since we took delivery of it three weeks ago.

First issue:

Battery charging voltage is showing 14.9V (measured with voltmeter across terminals engine on). Is this too high? What can cause this on a new boat?

Second issue:

When engine shut off and keys pulled out, tach remains at 500 or so for several minutes, and eventually goes down.

There are others...but I figure those are the two strangest.

The dealer is electrically inept. I have a lot of experience with automotive electronics, just a little out of my element on boats.

Please help...

Thanks!
Mike in Maine

 

[Silvertip]

Re: Electrical problems with new boat / Yamaha F50 motor

14.9 volts at the battery is a tick high but nothing to worry about. 16 - 17 volts is worrisome but even then only if you run very long distances. Although the charging system on an outboard is different than on a car, 12 volt systems are still 12 volt systems.

Just like some cars, gauges can "float" when the ignition is turned off. In the case of your tach that is perfectly normal.

What other problems does the boat have? One thing you need to understand is that there are essentially TWO electrical systems on the boat. The large battery cables going to the engine provide power for the engine and from there power is passed to the helm via the harness that runs to the control box. The gauges are powered from that circuit via the ignition switch. The second system is fed from the battery by a pair of #8 or #10 wires that feeds the fuse or circuit breaker panel. It is that circuit that feeds all other accessories. When troubleshooting work with the proper system. If accessories don't work, you need to look in the "boat" system. If gauges don't work or you have starter issues you are in the "engine" system".

 

[MikeMaine]

Re: Electrical problems with new boat / Yamaha F50 motor

thanks Silvertip

Im glad to hear the 14.9 is nothing to worry about.

Initially when we got the boat the main main Faria gauge cluster was mostly dead with gauges all over the place. The Lowrance depth finder was intermittently working. Operating the trim, nav lights etc. caused huge bounces in the gauges and the bilge pump was seized.

All those issues have been worked through now. Bad gauge cluster, loose grounds, swapped out seized bilge pump, bad Lowrance unit.

One more question - should all the electrical accessories work with no key in the ignition? From your earlier response it appears the answer should be 'yes'.

All that being said, the boat is great. 50HP Yamaha pushes it along at 35 MPH across the lake no problem.