Page 1 of 2 1 2 LastLast
Results 1 to 10 of 11
  1. #1

    Need help on wave venture 700 regarding compression...please read....

    OK, here is the deal....I got my carbs rebuilt last year by a place near me in NJ. They rebuilt the carbs last fall and I never used the ski because it had a broken wear ring. Installed the new ring, and winterized the ski properly.

    I NEVER ran the ski in the water still this year. Put it in the water and ran like crap, bogging, on low end, stumbling on high end so immediately went to pull ski out (ran 4 minutes max)..

    On way back to dock, engine locks up. Rear cylinder had 25 psi in it. Pulled motor apart, and had spare cylinder head and stock pistons and stock rings. Installed these correctly and have 125 psi per cylinder even on both.

    I know that 150 is about right for this motor and my main question is....Can I run the ski like this with no issues or do I need to get the compression higher. Both cylinders don't bleed down, hold compression. Runs good now that I rebuilt the carbs personally...

    Any help on this is appreciated. This is my second carb rebuild I've done and both run great. Guess wont need anyone to do the carbs now....

    Thanks in advance for the advice....also, what ratio should I premix at... Been told 44-1 some say 50-1 Just want my skis to run well and last.

    Thanks


    Don


  2. #2

    Join Date
    Jan 2014
    Location
    Chester, Va
    Posts
    74
    I'm no expert myself so I can only tell you what I've read on here by more knowledgable members. Apparently there's a high occurrence of blowing the rear crank seal when the 3rd piston goes. Again, this is only what I've read so someone else may chime in and prove me wrong. That being said, compression should increase once it's been broken in and the rings seat properly. 50-1 or 44-1 should be ok. Gonna smoke a little more at44-1 and probably foul the plugs out a little faster, but shouldn't hurt anything. May need to make small carb adjustments to compensate for the little bit of extra oil, but then again maybe not. Only way to know is to ride it.

  3. #3

    Join Date
    Jan 2014
    Location
    Chester, Va
    Posts
    74
    I run my 99 gp1200 at 32:1 which is recommended for that ski with mods. Smokes a bit but it keeps the Mosquitos away lol.

  4. #4
    Yamaha artisan Cutlass's Avatar
    Join Date
    Oct 2010
    Location
    Madison, WI, USA
    Posts
    2,500
    +1
    55
    125 psi is fine. I thought these were supposed to be 120 but I can't remember for sure. 50:1 is fine for a stock 700. Just use a good quality oil.

  5. #5

    Join Date
    Sep 2013
    Location
    Bennettsville, SC
    Posts
    888
    +1
    66
    125 is really low for a 701.......it will run for a while but not long. Personally, I'd put a top end in it. If you wait until it blows again, it may take out the crank also.

  6. #6
    I actually just did the top end of the ski. That's why I'm asking. I figured 120 was way low but will it hurt it to run it that way. All my others have 145-150 on the other skis

  7. #7
    Now I really don't know crap, lol. But i did a compression test on both my 94 wave raider 700 and 95 wave venture 700 last night. Cold all 4 cylinders (2 and 2) were around 120 +/- 1 psi. After idling up to operating temperature they are were 112 +/- 1 psi when the test was performed again. I just wanted to update for future reference that the compression test was performed again with a different gauge and all cylinders were 153 +/- 1 psi.

    Could I have not performed the test correctly - yes
    Could the gauge not be accurate - yes, but probably not.
    I'm sure there are other variables but these are my results and I was glad to see all cylinders were well with in the 10% range of each other. To me this tells me that they have all worn about the same over time.

    The wave raider may have lost a couple of miles per hour over the last 20 years, but it isn't noticeable and the hole shot is still there like it always has been.

    For what it's worth....
    Last edited by gtoffme5; 07-15-2014 at 02:26 PM. Reason: Compression Test was redone with a different gauge

  8. #8

    Join Date
    Sep 2013
    Location
    Bennettsville, SC
    Posts
    888
    +1
    66
    Sounds like y
    ou need a new compression gauge. To do a proper test remove one plug at a time. Hold the throttle wide open and wind the motor until the gauge won't climb any more. Reinstall plug, and repeat for other cylinder. If you didn't hold your throttle wide open you will have low readings

  9. #9
    Bean - I borrowed the gauge from the top mechanic in the shop, it looked brand new and had the proper fitting adapter for the jetski. It had a range for 0-300 psi.
    I removed both plugs to perform the test, but I did hold the throttle wide open and wound until the gauge wouldn't climb any more. Would removing both plugs first have caused a lower PSI reading? That is how the literature I was following said to do it.

  10. #10

    Join Date
    Sep 2013
    Location
    Bennettsville, SC
    Posts
    888
    +1
    66
    People do it both ways. Yamaha says to remove both plugs, many leave plugs in and remove I need at the time. The motor turns faster with plugs in, they say. I would say your gauge is suspect. If he is the "top" mechanic in the shop. ....stands to reason he would not lend out his "good" tools. I certainly wouldn't. Go ahead and buy a good one. I personally use the Innova from OREILLY's. I got the best one they had.....ran about 60 bucks.

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. Clean out nipple on wave venture 700
    By dontknowcrap in forum Yamaha PWC Performance (2-stroke)
    Replies: 0
    Last Post: 09-08-2016, 06:57 PM
  2. Need help with info on carb rebuild...wave venture 700 62T with dual minuki carbs
    By dontknowcrap in forum Yamaha PWC Performance (2-stroke)
    Replies: 4
    Last Post: 06-15-2014, 07:38 AM
  3. need help on 1050/900/700 pistons and cdi info
    By brent9k in forum Polaris Open Discussion
    Replies: 6
    Last Post: 05-14-2010, 04:20 AM
  4. need help on a SLT 700 Polaris
    By slt in forum Polaris Open Discussion
    Replies: 2
    Last Post: 06-05-2009, 12:12 AM
  5. Need Help On A Custom 320+HP Project Please!
    By ride_hyperlite in forum Sea Doo Open Discussion
    Replies: 1
    Last Post: 04-12-2009, 11:06 AM

Posting Permissions

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