Need help with cavitation on and 03 GTX.

[bell99man]

I have replaced the boot, carbon ring, and carrier ring. I replaced the deeply grooved wear ring. I put silicon around the 4 screws for the wear ring. I even put silicon behind and in front of the neoprene seal. The pump housing does have 2 cracks in it on the inside on the mating edge. They are about an inch long and are straight out from the edge towards the rear. I even put silicon here. I first thought the housing was weak and flexing causing pressure loss but the new wear ring still looks perfect. Before I pour another $400 into this project, are there any other possible air leaks? Ride plate screw? Intake grate screws? That little hose with a 90 degree turn on top of the pump? The plate on the transom the pump attaches to? Have any of these ever been the cause or do I just need to suck it up and replace this housing?

 

[bell99man]

I thought maybe someone would have some thoughts on this but in the mean time, I can't ride due to my back. BUT, this gives me plenty of time to research pumps and cavitation. I thought that a large number of these pumps were interchangeable so I would love for someone familiar with that to just clear up what is available for the 03 GTX std. I have found various lists with different overlapping years so I'm not sure which way to go. Thanks for any help.

 

[delonnelj]

Did you file the Impellers edge back smooth?

Silicone on a crack will not suffice. The pressure will expand the crack as you accelerate. Silicone not stop the expansion.

I'd file the Impellers blade edges. That rock may have changed the pitch on a blade. Those two occurrences will absolutely cause cavitation.

 

[AircraftDoc]

What does the impeller leading edges look like. They should be smooth to a cutting point. Otherwise, take it out and grind it down.

 

[bell99man]

New pump it is then and while it's out I'll clean up the leading edges all the way around. I've seen worse but I'd rather be thorough.