wear ring damage

[gearren]

I have a 97 seadoo challenger jetboat that I installed a new 13/21 solas concord impeller and wear ring, for better low end performance. After 20 hours of clean running the wear ring is shot! Large pieces if the nylon lining are missing, little pock-mark like holes in the substructure of the ring. The impeller is clean, no nicks or wear. I installed another wear ring, thinking I sucked up something, or possibly defective wear ring. I have 10 hours on the new wear ring, and I notice 2 small pebble size spots where the nylon is gone! I figure another couple of hours, and I'm pulling the pump AGAIN! Could this be cavitation damage? Is the solas 13/21 too low? Any ideas before I spend another $40 on a wear ring?...Mike

[Technical Support]

What clearance do you end up with after the ring installation? What are you using between the ring and housing?

[Bill O'Neal]

Yes, cavatation causes the pock marks and the destruction of the wear ring.
Send your impellor to Impros and tell David of your problem. He can fix it for you.

[gearren]

Bill,

The impeller is brand new! Is it possible that it came from the Solas plant out of round? Maybe I need to call Solas and see what they say.

Bryan,

The impeller rubbed lightly on one side when installed, but could be turned easily by hand. Review of forum indicated that slight "egg shape" was not uncommon, and would wear itself in. I tighten the bolts criss cross slowly working them to spec torque. Each time I install the housing, I use a new OEM neoprene seal. I also replaced the carbon seal and bellows. WHEN this wear ring finally gives it up, I am going to go back to the stock impeller and see what happens. I'm going broke chasing gremlins on this boat!

[Bill O'Neal]

My guess is that your new impellor is not the best choice for your jetboat.

GTX's and larger watercraft, like the jetboats, are very touchy about the impellors and cavatation. The heavier the craft, the more critical it gets.

The only solution I have found for Jetboats is to use a Skat Trak Swirl impellor in them.

[ June 14, 2003, 10:44 AM: Message edited by: Bill O'Neal ]

[gearren]

Thanks Bill,

Your advise has been on the mark EVERY TIME. What pitch on the Skat Trac would you recommend? Any recommendations where to get a fair price?

[pencil06]

How many more rpm are you pulling with the aftermarket impellor????

Spinning impellors to fast ( ie over 7,000 rpm)
Causes the water to boil at the edge's of your impellor, causing exactly the same fault.

Also do you spend much time out of the water, jumps or tight turns and have the engine out on the limiter... this will also cause pre mature failure of the wear ring

Broken engine mounts can also cause the engine to move allowing air pass the carbon seal, once again with the same result.

Regards Rick ...NZ

[Bill O'Neal]

New Skat Trak impellors are $209.95 at WCM. You need a 14x22.5 swirl, I think.

[gearren]

Pencil06,

I don't know the exact rpm, tach is off, but the rev limiter kicks in when accelerating during hole shot, and when try to go to WOT. I think you have given me the needed info to justify (to the boss) purchasing a new impeller.

Bill,

Thanks for the info, I will be in contact for the Skat Trac impellor.