Cavitation problem

[Jplasket999]

Wanted to get some peoples opinions here so here’s the story.
I have a 2019 gtx limited 300. 66 hours on it.
Last year the last day I rode it the ski kept cavitating on launch. Would accelerate perfectly fine after launch and reach top speed no problem. Only when launching from a dead stop it kept cavitating. I took it to Hamilton Yamaha to winterize it and I told them what was going on and they replaced the wear ring stating that was the problem. It was shot so it did need a new one. Fast forward to last week I take it out for the first time and it still cavitates on launch. So I took it back to Hamilton last week and they looked at it right away. He replaced the carbon seal that was bad they took it out in the water and it is still cavitating. He said jet pump and impeller look brand new no problems that would cause cavitation. So what else is left? Does anybody have any ideas?
Recap, only cavitates from a standstill on launch. That is it. Half throttle accelerates normal. And after 10 mph accelerates normal no problem. Hits top speed no problem.

 

[skiasylum]

If the wear ring was damaged, needed replacement, you sucked something hard between the impeller and wear ring. If they replaced the wear ring with a proper OEM ring the next place to check is a bent or damaged impeller blade, with 300 hp pulling water thru a 10” hole it needs to be near perfect not to cavitate. It needs to be measured.

 

[Jplasket999]

If the wear ring was damaged, needed replacement, you sucked something hard between the impeller and wear ring. If they replaced the wear ring with a proper OEM ring the next place to check is a bent or damaged impeller blade, with 300 hp pulling water thru a 10” hole it needs to be near perfect not to cavitate.

If the wear ring was damaged, needed replacement, you sucked something hard between the impeller and wear ring. If they replaced the wear ring with a proper OEM ring the next place to check is a bent or damaged impeller blade, with 300 hp pulling water thru a 10” hole it needs to be near perfect not to cavitate.

They took it apart twice now and both times said the impeller was fine

 

[Jplasket999]

If the wear ring was damaged, needed replacement, you sucked something hard between the impeller and wear ring. If they replaced the wear ring with a proper OEM ring the next place to check is a bent or damaged impeller blade, with 300 hp pulling water thru a 10” hole it needs to be near perfect not to cavitate. It needs to be measured.

 

[skiasylum]

If that’s the new ring, it looks like you already have a groove worn in the new ring. Hard to tell though the picture is pretty blurry. That would be caused by a bent blade or a worn pump bearing.

 

[Jplasket999]

If that’s the new ring, it looks like you already have a groove worn in the new ring. Hard to tell though the picture is pretty blurry. That would be caused by a bent blade or a worn pump bearing.

No the ring is fine that picture was just to show how little light was shining through the impeller. The more light you see the worse it would be

 

[skiasylum]

Carbon seal is next, if it’s wrong you will suck air from the engine compartment out the jet pump, and it doesn’t have to be leaking to cause cavitation.

 

[Jplasket999]

Carbon seal is next, if it’s wrong you will suck air from the engine compartment out the jet pump.

Like I said In my original post they just replaced that. Still didn’t fix the problem.

 

[skiasylum]

Oops, missed that, well that exhausts my knowledge on the subject, hopefully someone else pipes in.

 

[MacSeaDoo]

There are not alot of parts in the pump so if the pump has been checked and the carbon seal is new....Are you sure it is cavitation? Have checked all of your intake hoses and clamps? I had what seemed like a cavitation but was actually a bad coil.

Just a thought..

 

[Jplasket999]

There are not alot of parts in the pump so if the pump has been checked and the carbon seal is new....Are you sure it is cavitation? Have checked all of your intake hoses and clamps? I had what seemed like a cavitation but was actually a bad coil.

Just a thought..

Good idea but all other performance is perfectly normal. And the engine bounces off the rev limiter

 

[Cbrtrx]

View attachment 53340

That's a lot of light to see through, I cant even see half that much on mine. I'm guessing aftermarket wear ring with improper clearances.

 

[Jplasket999]

That's a lot of light to see through, I cant even see half that much on mine. I'm guessing aftermarket wear ring with improper clearances.

Nope like I said seadoo installed it. They’re going to change the impeller and go from there

 

[Cbrtrx]

Nope like I said seadoo installed it. They’re going to change the impeller and go from there

Just because they installed it dosent mean it's not an aftermarket one but if it's a factory one then something else is out of spec there, that is a tremendous amount of light to pass through in that pic. Hopefully a new prop fixes it.

 

[Jplasket999]

Just because they installed it dosent mean it's not an aftermarket one but if it's a factory one then something else is out of spec, that is a tremendous amount of light to pass through in that pic. Hopefully a new prop fixes it.

Yeah we’ll see what happens I already made a claim with seadoo as well so if this doesn’t fix it they’ll either figure it out or trade me into a new one

 

[skiasylum]

That would be good way for them to lose their dealer license. Doubt they would take that risk.

 

[Jplasket999]

This is the old impeller

 

[MacSeaDoo]

So they changed your wear ring and carbon seal and just ignored that? The leading edge is completely curled back, which would completely disrupt laminar flow. The result would be cavitation.

I would be looking for a different dealer brother..