2001 Seadoo Utopia 185 200HP cavitation at low speed

[karent_utopia]

My 2001 Seadoo Utopia 185 200 HP seems to have vibration or cavitation only at low speeds ( 5 to 10 mph). Runs great at 10-35+ MPH and can shoot out of hole with tubing no problem. Engine runs fine. I pulled the impeller and it only has a few minor dings ( see attached) and the wear ring looks fine. Any ideas what else could cause this low speed cavitation/ vibration problem? stator assembly ?

 

[karent_utopia]

Hi - I cleaned/ polished and removed burrs from the impeller and replaced, but still have a noise ( albeit on dry land) which sounds like something is loose .
Can you take a listen to this video and tell me what you think the noise is from ?

 

[karent_utopia]

Any ideas ?

 

[karent_utopia]

cavitation cause ??

 

[Tim75]

Sounds just about like my boat. I have always thought it was the tiny amount of slop in the gears. Mine sounds fine in the water with a constant load.

Cavitation in a jet boat is usually a leak somewhere on the intake side. Air is easier to suck in than water. A pin-hole will make a difference. Usually causes over-revving the engine with severe performance issues. Perhaps a leak between hull and jet casting? Is the large o-ring on the wear ring in good (elastic) condition or hard and stiff? I hate to think you could have a cracked casting.

Your impeller is not at its best. Those dings are enough to cause some cavitation.

 

[karent_utopia]

thanks! .. I will check it out ...., now wondering if the cavitation is from the forward bearing on the impeller shaft. ...

 

[karent_utopia]

thanks! .. I will check it out ...., now wondering if the cavitation is from the forward bearing on the impeller shaft. ...

wear ring looks fine

 

[Tim75]

thanks! .. I will check it out ...., now wondering if the cavitation is from the forward bearing on the impeller shaft. ...

Not sure why you think that but..............
Check the oil in the gearbox. If it is clear green, you should be OK. If it is brown and creamy, you may have a bad seal. Not sure if a bad bearing would cause and air leak.

Have you had your boat in the water since working on impeller? We may be worried about what was a problem.

 

[karent_utopia]

Thanks for your reply. Old fluid was an green in stator ( but I replaced at beginning of season) .
Boat was winterized after working on impeller.

As I don't think there is a bearing in the stator, so instead I was thinking about the bearing in the front ( see attached pix part #16, but this require removing the complete jet drive and possibly special tools .

Does anyone know of any repair shops that work on Jet drives in (southern) New England?

 

[Tim75]

Thanks for your reply. Old fluid was an green in stator ( but I replaced at beginning of season) .
Boat was winterized after working on impeller.

As I don't think there is a bearing in the stator, so instead I was thinking about the bearing in the front ( see attached pix part #16, but this require removing the complete jet drive and possibly special tools .

Does anyone know of any repair shops that work on Jet drives in (southern) New England?

As a matter of fact, there is a bearing in the stator. Known as a "plain bearing" or more commonly as a "bushing". Just behind the shaft seal in the stator housing.

Google "Mercury m2 jet service new england."

 

[SKutopia]

a delayed "thank you "

 

[Tim75]

My 2001 Seadoo Utopia 185 200 HP seems to have vibration or cavitation only at low speeds ( 5 to 10 mph). Runs great at 10-35+ MPH and can shoot out of hole with tubing no problem. Engine runs fine. I pulled the impeller and it only has a few minor dings ( see attached) and the wear ring looks fine. Any ideas what else could cause this low speed cavitation/ vibration problem? stator assembly ?

Those are not minor dings. That impeller needs attention including balance. While your impeller is off, replace the stator and check the shaft for straightness. Use machinist test indicator.

 

[SKutopia]

thanks !

...but are you saying to replace the 2 stator bushings or the entire stator ?

 

[Tim75]

thanks !

...but are you saying to replace the 2 stator bushings or the entire stator ?

In the stator--
Replace both plastic bushings and seal and seal protector and new oil. Make sure your oil drain screws and gaskets are in good condition.

Make sure the end of the impeller shaft is in good condition. Smooth, no nicks or dings or scratches.

 

[SKutopia]

thanks