Seadoo cavitating

[subdive4]

Looking for someone that might be able to explain.......

I took my 2000 Gtx out last weekend, it was running perfectly, then all of a sudden in deep water i did a little turn and went to accelerate again and the seadoo wouldnt go anywhere. like as if when the intake is plugged with weeds, the enginge would rev up and i could tell the impeller was turning, sounded exactly like when there is an obstruction, but there wasnt. I pulled it out of the water made sure there was nothing in the intake as well as checked out the impeller, everything was fine, no dings on the impeller at all? so i put it back into the water, still ran the same. But i soon found out that if i sat there and let if rev for about 20 secs, all of a sudden something would kick in and it would take off and speed right up (but still not to top speed like earlier in the day). this does not make sense to me? its direct driven by the shaft, could the impeller be slipping on the shaft?

 

[derek]

i think the pump develops an air leak at the front of the pump-where the wear ring mates to the hull. pull the pump off and put a nice fat bead of silicone-about a quarter of a tube-around the ring where the pump sits against the hull. bolt it back up and try it. then please let us know the result.

 

[Goddo]

Does the 2000GTX have the Neoprene seal?

If it has the seal, it's possible that the seal blew out or wore enough to cause water to leak and bypass the impeller.

My 95 had this problem eariler this year. Put on a new seal ($8) and just like new again. I'd pull the pump and have a look at how it meets the hull.

I'm planning on doing what subdive has suggested soon. At the same time I'll get my impeller touched up and she should go like mad.

 

[derek]

there is a lip on the front of the wear ring that looks like the lip on an oil seal. it is supposed to seal, but it can leak air in, especially after sucking something up. cause then you are fighting it with a high amount of suction. i found RTV-ing up the wear ring-to-hull face did the trick.

 

[subdive4]

Thanks for all your tips guys!
im no mechanic but i will try to take apart the jet pump etc to see what going on.

question? if there was an air leak, where would it come from, there is just water in and around the hul while in the water?

 

[subdive4]

Cavitation

Ok guys, i pulled the jet pump off no problem. the impeller,wear ring and neoprene seal look pretty good????? The only thing that looked a little off was a portion of one of the leading edges of the impeller was folded in a bit, dont know if just a little thing like that would cause the cavitation.....if not what else could be causing the cavitation?

Almost forgot, when i took it apart i found that there was no oil in the jet pump? im assuming that there would be oil in my 2000 gtx and not grease, but would this really matter?

 

[nswillin]

Hey sub. You must have oil in the jet pump or your bearings will fry. Check the oil by removing the small allen screw on the nose cone. It should be to the bottom of the threads. Only use
**NOTE: Use Sea Doo 75w90 GL5 Synthetic Polyester Oil, or similar.
That impeller is unbalanced and will vibrate and could damage wear ring, impeller shaft, shaft seal or bearings. One blade folded over will cause cavitating.
You could get it fixed cheaper than buying a new one. You could get a reconditioned one from SBT.