Other Pump cavitation when warm

[jadrian]

So I'm wrenching on a buddy's wave runner. It's a kawi st750. The ski runs fine cold but when it's warm it cavitates. It's done this on about 10 different occasions on different bodies of water. I started looking at the pump and the plastic intake guide that runs water into the pump is all broken up. The impeller doesn't look great and neither does the grommet that goes between the impeller and the drive shaft. Anyone have any suggestions on where to start? Do I have to break that intake guide out of there to install a new one or is that something I can fill in with epoxy or something else?

Thanks

 

[Tyrant1919]

Prop has a good deal of space between the wear ring and prop. Prop looks beat to . That hole you have pictured is probably where you're getting air into the pump. seal that hole or replace that part. You covered everything pretty much.

 

[jadrian]

Anyone have any tricks to seal that space? Was thinking maybe spray foam the big gap, cut it down then epoxy over it?

 

[stagesrt4]

you cant reseal the space... it would require new wear ring

I have a solas impeller for 750 laying around thats in much better condition then that one if you wanna give it a try.

that impeller is pretty beat but you can trying cleaning up the edging if your trying to be super cheap fix

 

[tor*p*do]

Anyone have any tricks to seal that space? Was thinking maybe spray foam the big gap, cut it down then epoxy over it?

that would work if you use fg cloth + epoxy

 

[stagesrt4]

you cant reseal the space... it would require new wear ring

I have a solas impeller for 750 laying around thats in much better condition then that one if you wanna give it a try.

that impeller is pretty beat but you can trying cleaning up the edging if your trying to be super cheap fix




as for the pump shoe being broke, you 'should replace' but can always try to backfill it with a tube of silicon ha

 

[N3vrSat1sfied]

seal that hole that is certainly a problem point that will allow the pump to suck air. I would also check prop to wear ring clearance .2-.5 mm

 

[jadrian]

Alright thanks. I might just chisel that intake guide out and glue a new one in. Do you know what type of glue to use on that? And for the prop clearance do you check that with a gauge or something else?

 

[N3vrSat1sfied]

Alright thanks. I might just chisel that intake guide out and glue a new one in. Do you know what type of glue to use on that? And for the prop clearance do you check that with a gauge or something else?

fe el ler gauges. Why the X thinks thats a cuss word is beyond me though lol

 

[CARBONX2]

Pumpshoe can be filled with epoxy putty, I have done it on an SXR

 

[jadrian]

I have a solas impeller for 750 laying around thats in much better condition then that one if you wanna give it a try.

Thanks man. Going to replace the shoe first and test it out. If it still runs like crap then I'll hit you up.