Vibration when surfing

[SteveK]

Hello everyone. I have a 2005 21V. I've only owned it for one season and surfing is new to me. I finally got my surf wave figured out pretty well. Centre bag mostly full, port side rear bag full and we had about 6 people in the boat. Wave was all washy but once I hit about 10 mph it cleaned up and I got a nice roller going.
My concern is that it seemed like as soon as I got that wave dialled in I noticed a vibration/howling. I couldn't tell where it was coming from except that it was from the stern. I have read that it's just prop vibration and it's nothing to worry about, but I'm paranoid about my transmission and v-drive (probably because this is my first v-drive boat and I'm not too familiar wit these).
Input, advice, tips?
Thanks,
Steve.

[spydermonkey]

i have a 2006 21v the growling/vibration is normal on mine when listed for surfing i have had the boat for 4 years no issue. last weekend i made a quick ghetto gate and am not listing anymore. the growl is gone and the wave is night and day make yourself a gate you will be amazed i didnt think it was possible to get a wave like this on a 21v. i was looking to replace the boat because we only surf now very thankful i dont have to, wish i would have made one sooner. i have only made one for regular surfing so far, love my boat again.

[CJD]

Every time I've had a vibration, it was because the prop was bent. Sometimes the bend is so slight that it only occurs at certain speeds.

When turning under high power/low speed it's normal to feel a pulsing on the helm...but that is the only place you feel it. The boat should not vibrate. My local prop-shop only charges $100 to true my props...so this off season you may want to put that on your list of things to do.

[SteveK]

Thanks for the replies. To clarify yes not a rattle or vibration from the helm. It's from the back. And it does seem to worsen when it lists more. As for the prop, the one on there was damaged and repaired by the previous owner but I've never felt any vibration from it and it still looks good. Repaired but good. I do have a new one so maybe I should swap.
And I've heard these ghetto gates mentioned but have not seen them. Anyone post some pictures or links for these?
Thanks again for the replies.

[blackout_58]

If it is any consolation, I had to have my prop repaired on my 21V and noticed a vibration. I recently put on a new 1235 and there is no longer and vibration when running center bag full and pet 1100 full. Like CJD said, you may want to consider either checking your prop or in my case replacing it.

[Wrenhaven]

And I've heard these ghetto gates mentioned but have not seen them. Anyone post some pictures or links for these?
Thanks again for the replies.

+1 Curious to see if this would be a good winter project!

[wotan2525]

If the vibration is only their when surfing or listed then it's not the prop. A damaged prop would show up when you were unweighted (but it might show up at a different speed/RPM combo.)

That being said, it wouldn't hurt to pull it and have a shop inspect/balance it. Cheap way to cross that off the list.

My theory -- the swim platform is either a little loose or just shaking at that speed. Have someone sit on your sun deck with their feet on your swim platform. I bet you a $1 it starts to buzz at that speed.

[2500HD]

One quick question, does it have a vibration when it is glass or just when it is choppy? My boat when listed and it is choppy will experience what could be called a shudder at times. It was prop cavitation. After switching to running level and using a wake shaper i no longer have this problem. I have since used both wake gates and then switched to a surf tab system. Look in the modification section for cornRickeys surfgate build thread for a wakegate or my DIY wakeshaper thread for surf tab set up.

[SteveK]

It seems to have more to do with the listing of the boat rather than the water conditions. After surfing for a while I could anticipate when it would start just by changing the weight around or when people moved around in the boat and it changed it's angle. My biggest worry was that it was the transmission or v-drive being run dry because of the angle it sits at when listed over like that. I do know the shudder you're talking about when I get into choppier water and it's different than that.
I did look and CornRickey's surfgate. Pretty impressive for a home DIY job! I might give it a try over winter.

[CJD]

As long as the fluid level is up, listing the boat will not hurt the V drive or tranny. V-drives fail with a "bang"...there is no doubt when they are bad. Tranny's make noise or slip so the RPM rises suddenly. They do not slip long before they loose all drive at all.