Cavitation problems

[Jetfish14]

Ive got a 99 superjet with a worx grate,stock pump,and impeller does fine on flat water but when u want to jump a wake it wants to cavitate. Rode my friends 08 superjet completely stock pump, impeller, etc and has none of the issues. Any ideas on what it could be?

 

[Tyler Zane]

I don't mean to insult your intelligence but cavitation can often be mistaken when it could be another issue.

Does it come out of the hole strong? If you do believe its a pump issue you need to start with a visual inspection on the impeller and wear ring.

 

[Shrivel]

Bad midshaft/intermediate housing will cause exactly this symptom.

 

[yamanube]

1999 Superjet impeller is a junk chunk of aluminum barely capable of propelling the ski past 1/4 throttle, it is only slightly better than having no impeller and allowed Yamaha to sell the superjet as a PWC and not as an expensive float toy. An aftermarket intake grate can exaggerate it's shortcomings.
The 2008 superjet impeller is a radial blade, large hub stainless steel impeller that is far superior to prior years.

 

[Pro-pulsion]

^^ What he said^^
Also the pump seal could be due for replacement. I just replaced mine last year because it was having a hard time staying hooked up. The new seal corrected all that and my ski is only 3 years older than yours.