Yamaha HPDI bogging with electrical signature

[shinola]

I have a 2003 HPDI 150. I have in the past been thru the fuel issues which cause bogging. I have a new issue that is very different and comes with an electrical signature. This may not be an HPDI issue at all, but I wanted to see if any Yamaha owners have seen this.

While running at cruise, ~2800 RPM, I will notice some of the dash gages begin to act erratically. Specifically, I notice the voltage begin to drop and the Tach gage to begin to act funny. Within seconds, the motor will begin to bog down and run rough, surging and ultimately stalling.

I'm able to get home each time, I may have to cycle the key switch a few times and let it idle a while until the gages begin to work again, then I can run at cruise again. This has happened twice each of my last two outings.

Any ideas? Where to start. I'm capable of trouble shooting, but I'm way more comfortable with mechanical issues than electrical.

thanks in Advance
Shinola

 

[boscoe99]

First thing that comes to mind is the battery cables connections. Clean and secure them at both ends. Don't use wing nuts. If a battery switch is installed then check the connections at the switch as well.

It would not hurt to disconnect and reconnect all of the couplers on the motor and at the helm as well. An 11 year old motor might have some corrosion starting to build up on pins and sockets within the couplers.

Also, remove, clean and re-secure (but don't over tighten) the many ground connection points on your motor.