Prop Slip ?? ... I think I broke something!

[SurfTN]

When you're in your 40s with young kids, a "guys surf night" can be hard to come by, but I got one last Friday (while others were chasing Pokemon in the park!). One of the guys needed to wrap things up a little sooner than the rest of us, so I was just going to run him back to the dock and then continue surfing. To save a little time, I switched off the cruise control and, while still ballasted to surf, made for the dock that was only maybe 500 yards away. When the boat hit maybe 15-18 mph I felt the prop slip (engine revved, boat slowed), so I backed off, got him to the dock and continued surfing without any trouble. Then later in the weekend I'm pulling my kids on the tube and at around 20-25 mph I start feeling an occasional "miss" of some kind, a little tug as if the tube were pulling the boat backwards but I know that's not what it is. It was subtle, but very apparent once I honed in on it.

I have a 2014 R20 with stock prop and the boat was heavy with ballast and people when it first slipped.

I checked transition fluid and all is good - just seemed like an easy place to start but I'm not exactly good at this stuff.

I'm going to make a call to my local inboard mechanic tomorrow, but wondering if this is an easy diagnosis.

[laserfish]

Wouldn't hurt to have it checked out, but in the past whenever we have done what you describe, it sometimes allows air under the boat and you get that funny rev when it hits the air pocket. Happens more often when it is a little rougher water.

[Cek1]

Sounds like prop cavitation. Mine will do it when weighted and doing tight turns.. Basically air bubbles create a void in the water creating no resistance to the prop. I'm sure some smarty pants will tell you the technical term and definition but that's basically it.

[Thegerman618]

Yep ^^^ X2 that's technical enough for this neighborhood. Tubes will cause it (especially in a whip), and when the boat is trying to plane with that much weight (surf weight) it will do it as well. Your golden SurfTN just a little cavitation.

Just a guess when pulling the tube it was a little choppy that day? It's seems to do it more frequently when it's choppy or going over a roller.