Seadoo Islandia Cavitation When Turning

[StanVA]

Looked to see if there was a thread already for this issue but couldn’t find one.
My 2001 Seadoo Islandia has cavitation when I make a right turn at higher speeds. No power lose on accelerating or any other time. When I’m turning left I can crank it as hard as I want with no issues. Just recently got this boat and the previous owner said it was an ongoing problem for him. Could it be the wear ring or should I be looking else where?
Thanks for the help!

 

[Tim75]

Looked to see if there was a thread already for this issue but couldn’t find one.
My 2001 Seadoo Islandia has cavitation when I make a right turn at higher speeds. No power lose on accelerating or any other time. When I’m turning left I can crank it as hard as I want with no issues. Just recently got this boat and the previous owner said it was an ongoing problem for him. Could it be the wear ring or should I be looking else where?
Thanks for the help!

There are several "Could be's".

Is your transom level when normally loaded and stopped? If your right side is already low when you start the turn, the left side can rise higher than it should and allow air under the hull to the pump. Do you have water sloshing in the bilge?

Is there a crack in the tunnel somewhere? Again, allowing air into the water. Lots of suction under the pump intake.

Between your wear ring and tunnel, there is an o-ring seal. Not visible unless disassembled. That seal area could be damaged or the o-ring damaged or missing. The forward face of the wear ring is suction. The aft face of the wear ring is pressure. A tiny leak at aft side is no big deal. The same leak on forward face could allow air into the suction side.

More about the wear ring-
The most important thing is the clearance between tips of impeller blades and wear ring. It should be about .02 inch. Every bit more, every deep groove is a loss of efficiency. Since the wear ring is soft cast aluminum, it wears first and fastest.

Stator-
The de-swirl vanes could be damaged. This can also cause cavitation. More likely to show up on initial acceleration.

Impeller-
Blade leading edge damage. Easy to check. Under the boat with a flashlight. Leading edge thickness should be about .015 - .020 inch. Thinner and they are easily damaged. Thicker and they are harder to drive through the water.

 

[StanVA]

There are several "Could be's".

Is your transom level when normally loaded and stopped? If your right side is already low when you start the turn, the left side can rise higher than it should and allow air under the hull to the pump. Do you have water sloshing in the bilge?

Is there a crack in the tunnel somewhere? Again, allowing air into the water. Lots of suction under the pump intake.

Between your wear ring and tunnel, there is an o-ring seal. Not visible unless disassembled. That seal area could be damaged or the o-ring damaged or missing. The forward face of the wear ring is suction. The aft face of the wear ring is pressure. A tiny leak at aft side is no big deal. The same leak on forward face could allow air into the suction side.

More about the wear ring-
The most important thing is the clearance between tips of impeller blades and wear ring. It should be about .02 inch. Every bit more, every deep groove is a loss of efficiency. Since the wear ring is soft cast aluminum, it wears first and fastest.

Stator-
The de-swirl vanes could be damaged. This can also cause cavitation. More likely to show up on initial acceleration.

Impeller-
Blade leading edge damage. Easy to check. Under the boat with a flashlight. Leading edge thickness should be about .015 - .020 inch. Thinner and they are easily damaged. Thicker and they are harder to drive through the water.

The boat sits level and the bilge is normal dampness but no standing water. The only time I get the cavitation is at higher speeds and harder right turns. I can take easy rights but that’s about it. I’ll try and check the impeller gap this coming weekend. There’s a bar missing out of the grate and one bent so I’m assuming the previous owner sucked up a rope from tubing or something and banged it up

 

[Tim75]

The boat sits level and the bilge is normal dampness but no standing water. The only time I get the cavitation is at higher speeds and harder right turns. I can take easy rights but that’s about it. I’ll try and check the impeller gap this coming weekend. There’s a bar missing out of the grate and one bent so I’m assuming the previous owner sucked up a rope from tubing or something and banged it up

I had similar issues in my Challenger. Hard turns at speed (left or right) and engine over-revving. Cavitation. I replaced the OEM impeller with a Solas unit. No more cav.