2003 Seadoo GTX cavitation

Trooper583

Petty Officer 2nd Class
Joined
Sep 19, 2010
Messages
134
Hello all,

In 2016 I bought 2 matching 2003 GTX limited models with super chargers with approx 130 hours on each. Both machines have ran great since I’ve had them in terms of the engines. Just before purchasing them the previous owner had them fully serviced including new wearing rings in the super chargers.

When I got them, one of them was incredible on take off, no “spinning out” or cavitation whatsoever. The other had a fair amount of this when you hammered it from a stop.

In the spring of this year I replaced the wear rings in both figuring that it would fix the one with trouble on take off and get them both on the same maintenance schedule.

However, when i reassembled them, the cavitation problem was still present on the one that initially had the issue. Also, the ski that was perfect before now has a slight “spin out” when you hammer it from a stop.

What should I look at first? Thanks!!

Sorry for the long post! I get long winded sometimes!!!
 

wahlejim

Master Chief Petty Officer
Joined
Jul 23, 2015
Messages
884
Impeller and wear ring is where I would start. Did you use OEM wear rings? The aftermarket ones can have slight variations in dimensions. What kind of shape are the impellers in? What pitch are they? Its possible a previous owner changed one to see performance differences and never changed them back.
 

Trooper583

Petty Officer 2nd Class
Joined
Sep 19, 2010
Messages
134
The impellers both looked good when I had them out and both of them will now run 61 mph in the top so I think they’re the same. I did use aftermarket wear rings. I think they were sbt? Or something. I did not replace the neoprene seal no did I put any silicone anywhere when I reassembled. Thanks for the response!
 

Brien S

Seaman
Joined
Nov 30, 2018
Messages
68
Also need to check wear ring to impeller clearance, and I would change the seal.
 

QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,286
Check the seal surfaces round the intake plate and grate.
 

JimS123

Fleet Admiral
Joined
Jul 27, 2007
Messages
7,952
Are you sure its cavitation? Those early SC models had a lot of issues with the superchargers. Maybe the problem is related to that. Just because parts were replaced doesn't mean the tech did it right.

Additionally, I believe because there were so many problems SD changed to ceramic parts, so you need to find out if the upgrade was done.
 

Trooper583

Petty Officer 2nd Class
Joined
Sep 19, 2010
Messages
134
The super chargers were changed over to the ceramic rings. Something else I failed to add...on the ski that ran great initially, there was a significant amount of silicone used to seal the pump to the transom. I can remember what condition the neoprene ring was in or even if there was one on them. The ride plates and such were sealed with silicone when I bought them. I think I’m going to put new pump seals on both and see what happens. Thanks for the replies
 

QBhoy

Fleet Admiral
Joined
Mar 10, 2016
Messages
8,286
Hope you get it sorted. But sounds pump related. If your wear rings are new...that’s good...but your prop also needs to be good too.
Pump sealing is a huge thing in all performance skis these days. Even to the point of sealing any tiny gaps between the intake and hull...etc etc. Any ski doing over 60 mph is all about marginal gains and components. Any one of these things letting the side down has a huge effect on the whole thing.
 
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