Other Spun Hub symptoms/questions

[bfan781]

Anyone want to take a stab at a few questions I have?
Can a spun hub act fine one minute and not the next? Is it one of those things where it can begin to fail at times and progressively get worse until it is completely shot? Can it cause hesitation during throttle until it catches? Almost positive I have a spun hub. Engine at times would rev real high, but the boat would not move. These are Spun hub symptoms. Other times it acted fine. Seems to be really bad last time out to the point i won't take it out again till its corrected.

Can it visually be inspected to determine if it is a spun hub without marking it and taking it out again?

 

[EricJRW]

Re: Other Spun Hub symptoms/questions

In terms of your symptoms, I can say sort of...

But in my own personal experience the prop worked fine below a certain RPM (it was about 3000 for me) and over that it would spin out, presumably as the forces on the prop increase. I could back off, and it would catch, and hold, as long as I kept RPMs below 3K.

The best way to confirm a spun hub is to make a mark on the prop that lines up with a part of the hub (for me I used the cotter pin, but I think that not all props use pins, so you might have to get creative, worst case being removing the prop and marking the hub - but if you can avoid this, it makes it so much easier). Depending on the color of your prop, a dab or two of nail polish or paint should do the trick.

Take the boat for a spin, and after the symptoms present themselves, check your marks. If the marks on the prop no longer line up with the reference on the hub, it's spun.

In lieu of that, a visual inspection may be telling, but it kinda depends on how much you spent spinning your hub. I severely spun my hope, because I had to limp home and I was doing this as fast I could. As such, I over-reved many times. When I got the prop off, I noticed two things:

1. The front of prop and the hub showed extreme wear. I assume this is because the bushing got soft and the prop was able to moved forward and was spinning at a different rate from the thrust washer.

2. The rubber bushing looked melted around the edges. Almost like the spinning caused friction, friction caused heat, and the heat caused melting. Poking at it with a finger and it was soft and sticky. Also the edges were no longer even. Compared to a new bushing it was obvious something failed.

While those clues might help, nothing beats the mark method. When I finally did it I only had to motor about 5 minutes and the problem presented itself.