Williams Jet Tender making weird sound

[captaindanhindsight]

I have a williams tender, which is basically a mini jet boat, or a rib jet boat. It is making a sound like it is coming out of the water even over the smallest waves. Has never done this before. Everything other than that sounds correct and the RPMs are correct. RPMs rev up when it makes the sound too and the boat feels like it is catching and slowing down on the water when it reconnects. Has anyone experience this type of thing with their Jetboat? I have attached a video so you can hear the sound. Any help is appreciated.

https://www.facebook.com/1348219487/posts/10225834209225751

 

[zipper]

Sounds like cavitation. What shape is the impellor in, any dings? Or possibly a line/fishing line wrapped up in it. Very nice tender BTW. I asume it is a Sportjet 520.

 

[captaindanhindsight]

Sounds like cavitation. What shape is the impellor in, any dings? Or possibly a line/fishing line wrapped up in it. Very nice tender BTW.

Havent had time to check it. Just pulled the tender off and now our boat is in dry dock so no good way to check the impeller or lines. In a murky marina in Guadeloupe. Dont think it is lines or I dont think I would still have normal acceleration. Could be the impeller. Going to have it serviced in St Martin, but will check those when I put it back on deck when we are out of dry dock. The strange thing is that it only happens when hitting a wave, even a very small one at speed. Otherwise it operates as normal. Thanks on the tender comment, it is super fun and fast, though any rigger or yard person says I should sell it for a normal tender, but it's just too much fun. Couldnt find anything via regular search, but my wife had a good point. Most people with these tenders just send them in when there is a problem an dont try and figure it out themselves.

 

[zipper]

You say put it back on deck...I have to ask, how big is the mothership to put a 17' tender on? Stick with the jet, we love our Zodiac cadet aluminum rib with the 15hp Mercury OB, but a center console type of rib jet tender would be a nice addition to the fleet. Good luck in St. Martin. Sailing there is on my bucket list.

Welcome to the Forum.

 

[captaindanhindsight]

You say put it back on deck...I have to ask, how big is the mothership to put a 17' tender on? Stick with the jet, we love our Zodiac cadet aluminum rib with the 15hp Mercury OB, but a center console type of rib jet tender would be a nice addition to the fleet. Good luck in St. Martin. Sailing there is on my bucket list.

Lol. Mothership is a Jeanneau 64. We are named Hindsight. Have a website and all if you care to take a look. Use out spinny pole to hoist it onto the foredeck. Looking into davits though because 500kg on the foredeck sailing really hurts performance.

 

[zipper]

Post a link, or do i just search S/V Hindsight. Us Northeners are stuck on the frozen hard and waiting for May to splash. Living vicariously thru others' boating until then.

Edit: I think I just found you... Come Sailing With Us!

 

[captaindanhindsight]

Post a link, or do i just search S/V Hindsight.

www.sailinghindsight.com couldnt believe it was available when we named the boat. Guess you get lucky once and a while.

 

[zipper]

Hopefully others more familiar with the Rotax 4-TEC 200 engine/jet will chime in with any additional information. If we had pictures or a video of the "sound" we may be able to help more. Is this a new issue? And one other, what is your draft with the wing keel?

 

[captaindanhindsight]

yes it is a new issue. Did the facebook link not work for the video and sound? Our draft with the wing keel is 2.6 meters, so can get in a lot more spots than if you had the regular keel which is 3.3+ meters which really limits your destinations. What sailboat is that in your pictures?

 

[captaindanhindsight]

And I will push it. will go to 1 meter or less under the keel before anchoring. Guess just had too much time being that shallow that i dont worry about it too much. Also dont have to put as much scope out at that depth.

 

[zipper]

No, the Facebook link is broken...



That is what I see. I was diagnosing based on your post, without the benefit of video.

We have an older cousin, ours is a 91 Beneteau First 35s5, we draw 6'10" deep fin lead keel with a tall rig

 

[Julian]

If its only cavitating when you hit a wave, I wonder if the engine mounts are loose? Just sounds like cavitation possibly due to impeller gap....???

 

[zipper]

@captaindanhindsight Can you upload the video to youtube and post a link here. Sometimes facebook links do not work here, for some reason.

 

[captaindanhindsight]

So figured out the problem. Had put a double safety line between the two front pad eyes. This left some line under the tender going horizontally. Don’t know exactly why but somehow that line was creating enough turbulence under the boat when on a plane to cause the symptom I was having. Strange but at least it’s fixed.

 

[zipper]

Good to hear that was all it was. How long are you in that floating dry dock?

 

[captaindanhindsight]

Probably until Mon or Tues.