Anyone running L13 + twin screw impeller + surfing in AR195?

[Ribs77]

Long story short, I've been dialing my wave in the AR195 for the better part of two seasons now. I can make a good wave, and with the L13 cone I can get the boat up to 10.5 mph, but I'm still getting some weird vibrations/cavitation at times.

It's not something stuck in the impeller - after draining ballast, I took the boat up to 40mph and 7400 rpm with two passengers and there was no vibration / cavitation. (I think it would go faster if the hull was clean, but it's wet-slipped and I don't pull it out to clean it very often.)

Anyway, the cavitation on launch really bothers me, mainly because it takes pretty precise acceleration to get to surf speed without cavitating, even with the cone. I have RideSteady but the cavitation also impacts auto-launch to the point that I can't use it.

I'm thinking about going to the twin screw impeller in the offseason, but I read a post on here about that impeller impacting his single-engine wake in a negative way. The poster said he could no longer surf ropeless with the twin screw impeller!

That would defeat the purpose of the whole thing, so I definitely want to be sure I can make a (relatively) great wave with the twin impeller. I can't find the post anymore, so I'm wondering if anyone else has run this setup.

So, the big picture.

AR195, L13 cone, about 1,000 lbs. ballast plus 2-3 passengers. If I add the twin screw impeller to this mix, will I keep the surfable wave but lose the cavitation?

Please help, it's driving me crazy

 

[Rinker2Yamaha24]

Hey! Thing we've talked on here before. I can some frame of reference... I have a 2021 AR190. For surfing, I use a 375 under the port cushion, 375 on top, and a 375 on the back platform. Wakebooster and ride steady with autolaunch. I have 0 cavitation and can surf all day with this set up 9.8mph is my sweet spot. that's with a buddy sitting in the back and me driving while #3 surfs. We're all 180-200lbs each. When I start adding folks I have to send someone to the bow to get to speed. Many more people I have to ditch the "on top of" cushion ballast bag. I'm at ~200 MSL.

The cavitation seems excessive... Maybe seal your intake tunnel and have you done a rebuild kit on plug recently? I did both when I bought my 2021 used this year. I still have the stock cone and stock impeller.

I would've thought the autolaunch would help with cavitation. Love that feature of the ride steady.

 

[anmut]

I know our boats are different, but just to give you a sense of how amazing the twin impellers are (bought mine from Leading Edge), I can put the full 750lb fat sac on the rear and run at 10mph with a few people in the boat at around 6400 rpm.

On my original stock impellers (which had some cavitation issues by the end of their life) I would be wide open at 7200 rpm to get to 10-10.5. There is an amazing amount of grab with those extra fins.

 

[Wicked92]

Get the impellar pitched correctly and there's no need for the l13 cone. They hurt my 255xd with twin scrolls.

I recommended leading edge, David Stewart. Used to own impros.

 

[Ribs77]

I know our boats are different, but just to give you a sense of how amazing the twin impellers are (bought mine from Leading Edge), I can put the full 750lb fat sac on the rear and run at 10mph with a few people in the boat at around 6400 rpm.

On my original stock impellers (which had some cavitation issues by the end of their life) I would be wide open at 7200 rpm to get to 10-10.5. There is an amazing amount of grab with those extra fins.

For what it's worth, when I get to speed (10.5) I'm running 5,800-6,000 rpm with 1,000 lbs. of ballast and ~2-3 passengers, including driver.

The issue is getting to that speed without cavitating! It requires a more delicate touch and takes longer than I want.

 

[Ribs77]

And I am more than happy to spend money on the twin impeller if it fixes this problem, but if it negatively impacts the surf wave I can't do it.

I just need someone to explain how/why the surf wave would or wouldn't be impacted by switching.

 

[Ribs77]

Hey! Thing we've talked on here before. I can some frame of reference... I have a 2021 AR190. For surfing, I use a 375 under the port cushion, 375 on top, and a 375 on the back platform. Wakebooster and ride steady with autolaunch. I have 0 cavitation and can surf all day with this set up 9.8mph is my sweet spot. that's with a buddy sitting in the back and me driving while #3 surfs. We're all 180-200lbs each. When I start adding folks I have to send someone to the bow to get to speed. Many more people I have to ditch the "on top of" cushion ballast bag. I'm at ~200 MSL.

The cavitation seems excessive... Maybe seal your intake tunnel and have you done a rebuild kit on plug recently? I did both when I bought my 2021 used this year. I still have the stock cone and stock impeller.

I would've thought the autolaunch would help with cavitation. Love that feature of the ride steady.

I have the 650 transom bag, so I use that plus 100 lbs. of lead in the surf side locker, and about 200 lbs. in the ski locker area.

I have tried sealing the intake tunnel, but I didn't remove the grate. It's possible I could do a slightly better job. The cleanout plug looks like it's in good shape - my boat is a 2021 also but I didn't see any wear around the seal when I looked at it recently.

 

[Wicked92]

And I am more than happy to spend money on the twin impeller if it fixes this problem, but if it negatively impacts the surf wave I can't do it.

I just need someone to explain how/why the surf wave would or wouldn't be impacted by switching.

The twin scroll won't hurt surfing, only improve it. It keeps the pump loaded, similar to how a intake grate works on wave runners. But if you have tunnel, sealant, pump plate and wear ring issues it can't fix those.

Cavitation sometimes is mistaken for ventilation, which is when the pump is able to pull air in from a source (clean outs, pump tunnel sealant, pump tunnel plate.... etc.

 

[Rinker2Yamaha24]

I have the 650 transom bag, so I use that plus 100 lbs. of lead in the surf side locker, and about 200 lbs. in the ski locker area.

I have tried sealing the intake tunnel, but I didn't remove the grate. It's possible I could do a slightly better job. The cleanout plug looks like it's in good shape - my boat is a 2021 also but I didn't see any wear around the seal when I looked at it recently.

I have the 650 transom bag, so I use that plus 100 lbs. of lead in the surf side locker, and about 200 lbs. in the ski locker area.

I have tried sealing the intake tunnel, but I didn't remove the grate. It's possible I could do a slightly better job. The cleanout plug looks like it's in good shape - my boat is a 2021 also but I didn't see any wear around the seal when I looked at it recently.

My thought here would be to take the grate off and seal all of it inside and see if that helps before dropping $$$ on a new impeller. I noticed a large improvement with my boat when I did it. You're going to be all up in there already when you replace the impeller. Just 4 bolts and reseal them with 4200. I used the loctite version they sell at lowes. used that one for years on my old rinker without issue below the water line.

I'm just glad I'm not the only one pushing a ar190/195 to do surf boat things. Its the biggest boat I can fit in my garage that checks the boxes.

 

[Ribs77]

My thought here would be to take the grate off and seal all of it inside and see if that helps before dropping $$$ on a new impeller. I noticed a large improvement with my boat when I did it. You're going to be all up in there already when you replace the impeller. Just 4 bolts and reseal them with 4200. I used the loctite version they sell at lowes. used that one for years on my old rinker without issue below the water line.

I'm just glad I'm not the only one pushing a ar190/195 to do surf boat things. Its the biggest boat I can fit in my garage that checks the boxes.

I'm thinking about this...

Do you also reseal around the perimeter of the grate when you re-attach? With the same sealant?

And to seal the bolts, you just put some of that crap on the threads before you re-thread? No threadlocker?

Edit: And yeah, high-five on pushing the 195 to the max for surfing! When I have good conditions and the wave is right, I feel like I've got plenty to work with for my skill level.

 

[Rinker2Yamaha24]

I'm thinking about this...

Do you also reseal around the perimeter of the grate when you re-attach? With the same sealant?

And to seal the bolts, you just put some of that crap on the threads before you re-thread? No threadlocker?

Edit: And yeah, high-five on pushing the 195 to the max for surfing! When I have good conditions and the wave is right, I feel like I've got plenty to work with for my skill level.

Here is what I took as gospel and it helped...https://jetboaters.net/threads/hero-or-zero-resealed-my-jet-pump.17845/

I did this at around 60 hours and I have 123 on mine now and it looks the same.

To clarify, I didn't re-seal around the grate after it was reattached, just a glob on the bolts when I bolted the grate back on. I want to say the 2 bow side bolts had sealant and the 2 stern side bolts did not. The stuff gets everywhere.. I used a little spray bottle of water on a mist mode to mist it like you would caulk and that helped me smooth it out. Still looks terrible, but its under the boat where no one can see! It really only took me 10 minutes.

Attached are 4 photos. I've pointed to the bolts took off.