190 FSH Cavitation

[Rich NW Jboater]

I noticed some cavitation on the upper RPM range this weekend with five normal sized adults onboard. So I searched through the threads and found that the sealant needs to be touched up every once in a while on the pump inlet so I get under the boat and take the intake grate off and notice that my clean out plug is portruding about 1/8 inch on the leading edge, perfectly flush on the aft side. Does anyone know if this could be the issue?

 

[Swood79]

My clean out port on my 2017 ar195 sticks down about the same amount and I have trouble with cavitation aswell. I tried to reseal the intake because some sealant was missing but there's still cavitation, this spring I'm going to take off the big plate behind the intake grate and reseal the whole pump completely. But I do wonder if that's standard for the the clean out port to be that low or if it needs to be rebuilt

 

[swatski]

My clean out port on my 2017 ar195 sticks down about the same amount and I have trouble with cavitation aswell. I tried to reseal the intake because some sealant was missing but there's still cavitation, this spring I'm going to take off the big plate behind the intake grate and reseal the whole pump completely. But I do wonder if that's standard for the the clean out port to be that low or if it needs to be rebuilt

Nothing wrong with filing/grinding the protruding edge flush with the tunnel, or as some call it "porting" the pump tunnel. Definitely helps to smooth it all out. But sealing any is the key, there are gaps in those pumps on the low pressure side (intakes) that permit air being sucked (into the tunnel) from the bilge. I would say most Yamaha pumps are probably not perfectly sealed.
There was a thread here (and posted on FB) by a guy who did an amazing job professionally porting a pump in his 192 with serious performance gains. I'll try to find it.

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[swatski]

My clean out port on my 2017 ar195 sticks down about the same amount and I have trouble with cavitation aswell. I tried to reseal the intake because some sealant was missing but there's still cavitation, this spring I'm going to take off the big plate behind the intake grate and reseal the whole pump completely. But I do wonder if that's standard for the the clean out port to be that low or if it needs to be rebuilt

Found it - this is the post with links to pics for WFO project.

Guys - there is crazy good writeup on the 192 mod project by YJB (old forum) member erj1452002 is posting there. AWESOME!!!

The way the WFO is doing his mods, he has surpassed a stock 195 performance already. Amazing.

What is amazing is they machined a lot of the parts to convert a standard 192 Yamaha 155mm pump into a 160mm impeller and wear ring, even managed to leave the "old" stator and transom plate. Must have redrilled the openings for the water channel, and the transom plate is beautifully tapered.
EDIT: never mind, they seemed to have bypassed the channel altogether.


The whole pump "blueprinting" is the work of art!

Also check out the cold air intake! The whole project is just freaking beautiful. Check it out!!!

Check it out:
https://www.facebook.com/pg/wfoperforma ... 1174084484

Too bad I'm not on facebook, I had to hack into wife's account to view your project. It is worth it but I am going to be in so much $hit when she find out.

He also posted some on instagram:
Login • Instagram

And on the old site:
Yamaha Jet Boaters • Login

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[Swood79]

Awesome! Lot of good pic on his Facebook. I wonder if it would be a good idea to use a more permanent seal rather than the standard clear silicone they used on my boat

 

[swatski]

Awesome! Lot of good pic on his Facebook. I wonder if it would be a good idea to use a more permanent seal rather than the standard clear silicone they used on my boat

Yes. I used epoxy caulk and bondo compound, again, I'll try to find my posts. Very happy witht he results, and when it gets warm I'm going to redo everything in the spring with epoxy paint finish. Sealing/porting the pump makes a huge difference. Another good aid is the L13 cone. Thiose work really well in a 190, actually kind of crazy well when used in combination with the factory (OEM) impellers.

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[swatski]

Here is another thread with some serious pump sealing - starting in post #72 or so.
See what @jcyamaharider did there, too, I think he had the same issue with the plug edge protruding inside the tunnel as in your case.

https://jetboaters.net/threads/pump-intake-grates-thinking-of-trying-something-taboo.15594/page-4

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[Rich NW Jboater]

Thank you all so much for the info and links to the threads. I resealed mine but haven't ran it with additional people on board yet. Might try to shave the leading edge of the plug if I don't get the desired result.

 

[Swood79]

Yes. I used epoxy caulk and bondo compound, again, I'll try to find my posts. Very happy witht he results, and when it gets warm I'm going to redo everything in the spring with epoxy paint finish. Sealing/porting the pump makes a huge difference. Another good aid is the L13 cone. Thiose work really well in a 190, actually kind of crazy well when used in combination with the factory (OEM) impellers.

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I installed the L13 cone on my 195 but I didn't notice much of a difference, but this spring I'm going to completely reseal everything and possible get a Solas prop or a new factory. With 5 guys on my boat it would take a good minute to get up to plane because I can't full throttle it without it cavitating. Even if it's only me on, I can't full throttle from a dead stop without it cavitating horribly. Is that just how these boats are?

 

[2kwik4u]

Is that just how these boats are?

Absolutely not. Something is awry on your boat. Mine (even being lower powered than your 195) launches like a scared cat on carpet. I've had 7 adult sized people and two coolers on board my 190 and still gotten a a boarder up from a deep water start.

I suspect an intake tunnel sealing will be fruitful for you. Once you have the L13, and the intake tunnel sealed, start looking at adjusting the impeller pitch. Might just have a slightly too aggressive pitched impeller. Think of impeller pitch as rear end gearing on your truck. Too aggressive and you get more torque than you can put down (cavitation), not aggressive enough and you don't get full revs under load

 

[2kwik4u]

Found it - this is the post with links to pics for WFO project.

Holy shitballs that dude did some work on his 192. I love that new intercooler with dedicated raw water cooling line, and the "cool air" intake setup he has to draw from the rear storage area. Any links to what kind of gains he saw with that work. Doesn't look like he increased airflow anywhere, but I bet it's SUPER consistent regardless of air and water temp.

Thanks for sharing. I missed that post the first time!

 

[swatski]

I installed the L13 cone on my 195 but I didn't notice much of a difference, but this spring I'm going to completely reseal everything and possible get a Solas prop or a new factory. With 5 guys on my boat it would take a good minute to get up to plane because I can't full throttle it without it cavitating. Even if it's only me on, I can't full throttle from a dead stop without it cavitating horribly. Is that just how these boats are?

THat's not normal., sounds like the pump is sucking the air from somewhere in the tunnel, it could also be a gap/missing sealant between transom plate and the transom.
I recall there was a thread by Jerry Gadis (owner of greenhulk forum) where he did some serious sealing a transom plate to the transom in one of his Yamaha jet skis and that cured bad cavitation.
I would start with scoping the tunnel really well, may need to remove the intake grates for some access, and use a phone, any gap with w/missing sealant could be a culprit.
Unless your impeller is damaged that's usually not an issue, just check the gap between the blades (trailing edge) and the wear ring, it should be very tight, I don;t recall the exact tolerances - posted somewhere here - but if a credit card fits easily it';s too much.

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[FSH 210 Sport]

THat's not normal., sounds like the pump is sucking the air from somewhere in the tunnel, it could also be a gap/missing sealant between transom plate and the transom.
I recall there was a thread by Jerry Gadis (owner of greenhulk forum) where he did some serious sealing a transom plate to the transom in one of his Yamaha jet skis and that cured bad cavitation.
I would start with scoping the tunnel really well, may need to remove the intake grates for some access, and use a phone, any gap with w/missing sealant could be a culprit.
Unless your impeller is damaged that's usually not an issue, just check the gap between the blades (trailing edge) and the wear ring, it should be very tight, I don;t recall the exact tolerances - posted somewhere here - but if a credit card fits easily it';s too much.

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According to my shop manual, the impeller clearance is .0138“-.0177”, with a limit of .0236”

 

[Swood79]

I stuck my head under the boat to check out the prop, it didn't look too bad, a couple of nicks but nothing major, and from what I saw it was pretty close but I could see light between the blades and the wear ring. My old Ski doo gtx had a replaceable wear ring, are these boats the same? Or do I not have to worry about that. I've heard about repitching the blades, is that something I have to send in to someone? My boat is all stock

 

[FSH 210 Sport]

I stuck my head under the boat to check out the prop, it didn't look too bad, a couple of nicks but nothing major, and from what I saw it was pretty close but I could see light between the blades and the wear ring. My old Ski doo gtx had a replaceable wear ring, are these boats the same? Or do I not have to worry about that. I've heard about repitching the blades, is that something I have to send in to someone? My boat is all stock

The wear ring is not replaceable from what I understand, you have to replace that section of the pump. The spec for that section of the pump is 6.116”-6.120”, the limit is 6.159”.

Re pitching the impeller blades depends on whether or not you live at high altitude, and are having a problem reaching peak rpm’s, or close to it.

 

[Swood79]

I'm in ohio so elevation isn't an issue, the boat gets up to speed, with myself on it I was 52mph. It's only the hole shot that sucks.

 

[FSH 210 Sport]

I'm in ohio so elevation isn't an issue, the boat gets up to speed, with myself on it I was 52mph. It's only the hole shot that sucks.

Right on that is moving right along.... may I suggest getting some feeler gauges and check the impeller to wear ring to verify you are within spec.

 

[Jmyers408]

I purchased my AR190 early last year and am now looking at some mods. Came across l13 pump cone but not sure exactly what model I need? Any help would be greatly appreciated.

 

[swatski]

I purchased my AR190 early last year and am now looking at some mods. Came across l13 pump cone but not sure exactly what model I need? Any help would be greatly appreciated.

This is the cone for 1.8 HO

GreenHulk PWC Performance Store - Lucky 13 Adjustable Pump Cone for Yamaha SHO/HO Skis & Riva Race Pump

All billet construction and hard anodized to prevent corrosion. Easily adjusted by removing stainless steel tail cone bolt, pulling off billet cone and adding or removing supplied spacers.The extended length of the Lucky 13 Performance Pump Cone allows for custom pump pressure tuning resulting...

www.4-tecperformance.com

I would email Jerry Gaddis <pwcperformancestore@gmail.com> directly, tell him you are a boater on this forum, ask if he can give you any discounts.

When you do your install, do not forget to swap the o-ring seal (or install a new one).