Axis Wakeboard Boat Forum

2014 A22, 3500 pounds of ballast, wedge down (on rear bolthole) 13.6 X 16 prop, 350 CID surfgate on right.

9.8 mph at around 3200 rpm in rough water.

So while making that huge wave for a daughter I heard and felt the boat shudder. It felt like a cross between "clutch chatter" and "torque converter shudder".

Any mechanics out there with knowledge of the v-drive internals? Is it a problem with overloading (over torque) causing internal slippage? Can the engagement be adjusted to ensure it cannot break into slippage? Is this a cry for a new prop that is larger/less pitchy to reduce torque load on shaft and better pull the weight?

New boat with only 25 or so hours.

Any help appreciated.

Wayne

Do you think the prop could have picked up some trash from the lake and shot it out pretty quickly? Mine has done that before. If it repeats itself anytime soon, then that is when I would worry. If it is an isolated event, I wouldn't worry about it. Did the boat lose speed during this "shudder"?

The event lasted several seconds, so I was not thinking about trash-induced cavitation at the time. I did wonder if I was leaning a bit and allowing the rough water to affect the prop'e clean water supply. I pulled back on the throttle and it recovered and then I got back on it and moved folks around for a better balance.

It happened a second time that day and the boat was level. The engine seems very near its torque limit, and I inspected the prop and it remains pristine. I did find some grass on the shaft between the strut and prop, so cavitation is a definite possibility, but it felt more like a worn automotive torque converter having a lock-up shudder.

The reason why I said it may be prop induced was cause I have had a similar type situation before on a previous boat I owned that was not an Axis. We had a lot of lake trash that year. Usually throttling down and it resolved the issue. I would check all the fluids in both the transmission and v-drive just to verify.

Im not familiar with that prop - are you sure its correct? I have the A22 with ACME 1235 (High Altitude prop) which I think is 14.5x14.25. I used to get that same "rumble" often last year when I used to surf tilted AND turning AND rough water. I also used to have a problem with my front bag draining on its own causing the nose to rise up. This prop cavitation NEVER happens anymore now that I am more level left/right and front/back. try adding more front weight in your situation.

Fluids good, just had first service.

I think I need a more "low end" prop. I bet this one is fine for wakeboarding speeds, but for surfing I have had issues with full tanks and full of people where I could not quite get up to speed with throttle wide open. The problem is that I dinged the old prop and got a replacement before the engine was broken in enuff for surfing, so I now have 2 of these props. I wish I had got the 'new' one as a high altitude or similar prop. I never really need to go above around 25 mph.

Also I was a little bow-up at the times in question. I have been playing with ballast trying to find the perfect wave... So that might account for some of it.

I just wish I could find a cheap grunting prop to test...

I took the old dinged prop to Wilmington Propeller and they changed it to a 13.5 X 14 (down from a pitch of 16). Now can wake surf with half the throttle of before. No where near torque limits and no cavitation at all.

When I get rich I will buy a new 15 X 12, but in the mean time this works so much better than what I had before!

I think its just trash in the prop mine does it from time to time and scares the crap out of me but it always goes away, clears up, and the prop is never dinged

I do not know if it was trash causing momentary cavitation or a slip induced by torque load, but I changed my prop pitch and everything is better. was 13.5 X 16. Had it rebuilt to 13.5 X 14. Throttle setting significantly reduced, RPM up, and no issue is operating at surf speeds with amazing weight in the boat.