Page 1 of 2 1 2 LastLast
Results 1 to 10 of 11
  1. #1
    cliff717's Avatar
    Join Date
    Jun 2009
    Location
    ontario
    Posts
    148

    cavitation need help!

    first off i would like to say how great of a sight this is, all the d.i.y info is awesome i have already learned allot. now to my problem. i recently purchaced a 04 rxp with 80 hours on it. from what i can see it is stock except it has a intake grate on it (maby riva).and the supercharger was just re-built. the ski runs great but the holeshot sucks. the pump seems to cavitate under acceleration and them bounces off the rev-limeter at aprox. 8200 rpm. the first thing that came to mind was the wear ring so i poped the pump off and the wear ring does not look that bad. there is no edge on it maby some slight rings but none any deeper than 1/16 an inch. the prop had some dings so i lightly sanded them out and made the prop smooth again. second was the carbon ring. so i did some research here and found the trick to put some quick ties in the acordian boot and that will tighten the seal up and it did seem to force those seals together but even with these two things done it still cavitates. i was thinking it may have the wrong pitch prop on it but it looks like the stock unit and it is spot on 8100 at full throtle so that makes me think the prop is correct. so does anyone have any ideas of what i should look at next? any help would be great
    p.s. sorry for the crazy long post


  2. #2

  3. #3
    cliff717's Avatar
    Join Date
    Jun 2009
    Location
    ontario
    Posts
    148
    thanks promod1955 in one of those links you were having the same problem as me. was it the carbon seal that fixed the problem? now when i put those quick ties in the acordian of the boot it did seem to put way more pressure on the seal yet it still cavitates. does this mean that the seal is good or could there still be air geting through? as far as i found from reading here; it has to 1 or 2 things either the wear ring or the carbon seal. how much wear can be on the wear ring before it starts to cavitate bad?
    thanks cliff

  4. #4

    Join Date
    May 2009
    Location
    Virginia Beach, VA
    Posts
    119
    +1
    2
    I havent had it out yet. Going saturday and hoping for the best. You could also have a broke fin in the pump shoe. the max distance between the wear ring and the impeller is .014" before it should be replaced. you need to pull the pump to do this.


    the skat trak seal has fixed a lot of peoples cavatation issues.

  5. #5
    cliff717's Avatar
    Join Date
    Jun 2009
    Location
    ontario
    Posts
    148
    the fins in the pump shoe? those are the small fins after the intake before the impeller? the ones that stay on the machine when you take the pump off. there is some damage there how do i fix that problem can those fins be removed and smoothed out or are they important? my yamaha did not have these fins.

  6. #6

    Join Date
    May 2009
    Location
    Virginia Beach, VA
    Posts
    119
    +1
    2
    Yes thats what im refering to. The damage will cause cavitation too. Take a dremel or air grinder ( like what you use to port cylinder heads) and remove all of them.

  7. #7
    cliff717's Avatar
    Join Date
    Jun 2009
    Location
    ontario
    Posts
    148
    ok removed all of them and sanded it smooth. i'm going to try it out soon thanks

  8. #8
    cliff717's Avatar
    Join Date
    Jun 2009
    Location
    ontario
    Posts
    148
    just an update. sanding off the fins got rid of about half of the cavitation issue so that was a great help. next i borrowed my buddie's pump and tryed it on my ski and cavitation ws totaly gone so the problem must be either my impeller or the wear ring. i am going to start with the wear ring and see if that does it
    thanks for all the help

  9. #9
    King_Of_Fun's Avatar
    Join Date
    Jul 2007
    Location
    Catawba Island, Ohio
    Posts
    2,703
    Hey, 1/16" = .0625" and the recommended clearance between the impeller and wear ring is .014", so you have more than 2 times the recommended maximum clearance. Time for a new wear ring... Ron

  10. #10
    lextoy's Avatar
    Join Date
    Jan 2007
    Location
    Brigantine, NJ
    Posts
    1,883
    +1
    14
    wear ring damage and dings in the impeller, are definitley a source of CAV.
    do the wear ring for sure.
    you can flip it you know???
    may want to consider a IMPROS impeller recondition. if it is a stock impeller, damage is 1st problem, 2nd problem is, from the factory, the impellers were notoriously off pitch.
    some have gained noticeable speed and rpm, from just getting their stock impeller properly tuned.
    example, 4 blades on an impeller
    each blade had a different pitch, 14/24, 12/22, 12/23, 14/22, thats gonna mess with impeller performance big time.
    once repitched properly to exact spec, lets say 13/24, the impeller will hook up awesome and perform better.
    how old is your ski, is it all stock???
    i only mention this cuz whuile you are pullin the pump and wear ring to flip it, might as well rehab the imepeller.

Page 1 of 2 1 2 LastLast

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Similar Threads

  1. 2015 FX SVHO Need Help...hesitation? Cavitation?
    By Sam SHO in forum Yamaha PWC Performance (4-stroke)
    Replies: 10
    Last Post: 05-27-2015, 06:05 PM
  2. 2007 Seadoo RXP Cavitation.. NEED HELP!
    By Inferno454ss in forum 4-Tec Performance
    Replies: 10
    Last Post: 07-05-2012, 09:04 AM
  3. Need help cavitation out of the hole
    By andre in forum 4-Tec Performance
    Replies: 19
    Last Post: 11-02-2008, 08:49 AM
  4. Bad Cavitation!!! Need Help!!
    By ArmyRXP in forum 4-Tec Performance
    Replies: 4
    Last Post: 07-08-2008, 07:46 PM
  5. new SS and cavitation...need help!
    By pet in forum 4-Tec Performance
    Replies: 44
    Last Post: 06-17-2007, 09:32 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •