Stator/ Spun Prop

[pastorrob1169]

I have a 50hp Merc that I recently replaced everything thing from the fuel tank to the carbs which fixed the bulb collapsing problem I had. The boat was running good. I did not run the boat for about a week and went out and the battery was dead. I replaced the battery and we went out and the boat ran great lots of cruising. I disconnected the terminal when we got back because it was arking when I connected it orignally and was told that something was draining my battery. The next day the boat started great ran fine on the way out with the current at a lower speed. When we were returning against the tide at higher throttle the motor would rev way up (I dont have a tac) but the boat would slow down. When you throttled down it would run ok and we idle back through the canals fine. I did turn around and ran with the current to see if it would do the same thing and it did. Could this be an electrical issue related to something draining the battery or maybe spun prop or even some sort of ignition issue?

Thanks

 

[Chris1956]

Re: Stator/ Spun Prop

It sounds like you have a spun prop and a bad rectifier. The spun prop is why the motor revs up, without pushing the boat at high speed. The bad rectifier is why the battery is going dead.

What year motor do you have?

 

[pastorrob1169]

Re: Stator/ Spun Prop

The motor is a 2005 3cyl. 50hp 2-stroke. We just moved to Florida from Ohio where the boat was not used very much due to the weather. I think that use and salt water is brining out any weak spots it may have had from the days of limited use. It had sat for 8 months winterized before being put in the water about a month or so ago. Is the part that breaks on a spun prop a rubber bushing and can sitting cause it to fail? Thanks for answering so quickly.

Robby

 

[Chris1956]

Re: Stator/ Spun Prop

Rob, I do not know what causes a prop hub to fail. Certainly hitting something will, but sometimes they just like to fail. Having a spare prop is a good idea, since sometimes the hubs fail completely and you can't even idle home...

 

[mgjtkt]

Re: Stator/ Spun Prop

I don't have that exact motor but my 1994 Merc 40hp is supposed to spark a little when touching the cable to the battery. Buy a OEM service manual from merc., they are expensive but beats guessing and replacing good parts.

 

[Chris1956]

Re: Stator/ Spun Prop

Your motor is not supposed to "spark a little" when you connect it. That indicates something is drawing current. it is either a short, bad rectifier or VR, or you have left something on.