1997 Seadoo Speedster cavation Problem

[mikeal71]

The boat ran fine the first part of last summer cavation problem developed quickly! The clearances on the pump appear to be good small amount of scuffs but nothing major. Cavation i understand can be caused by air being injected from some where is there a problem area i need to be looking at? i plan to replace the wear ring being i have it put down is this wise with no major wear areas?

 

[Bills86e]

A 140MM pump will cavitate after the impellor to ring clearance exceeds .040.
The edges become a cut instead of a mover of water, oxygen is released., and
the prop churnes in a large air pocket.