Results 1 to 9 of 9
  1. #1

    97 gp1200 fuel issue

    I bought a 97 gp1200 a few weeks ago
    Had been sitting for awhile
    Rebuild the carbs, it already had the primer kit installed
    Even with the primer it's very hard to get started
    All cylinders are 105 psi
    I set the jets to a recommendation I found on here
    Once started it runs good, except
    It wont rev past 3-4k, slow throttle increase or pinning it doesn't make a difference
    Now, if I give it one shot with the primer then hit the throttle it will rev up to full throttle just fine and stay there for as long as you want
    If I keep the rpms above 4k, then no acceleration issues
    But when I go back to idle it wont rev up without the primer pump


  2. #2
    Not even a smart a$$ comment?
    OK, I guess I'll mess with the high and low carb adjustments to see what happens

  3. #3
    Ok I will bite. If your compression tester is accurate then you compression is low and your probably need a new top end. You could also check that you are building up pressure in your gas tank. I would also double check that you reinstalled everything correctly in your carb.

  4. #4
    Thanks for the response
    Do you think the compression would really be a factor since it runs great on the top end?
    Just needs an extra shot of fuel to get there
    I put new needle and spring in that came in the kit.
    After more research it sounds like I should of left the old ones since my pop off pressmight be different now
    It will be about a week and a half before I'm back to the lake to check it out
    Just want to have an idea on what to bring for testing

  5. #5
    I know the primer was installed on the on side of the fuel system
    I have also seen most recommend installing it on the return line to avoid problems with the fuel supply
    Thought maybe that could be causing an issue too?

  6. #6
    raiderteen's Avatar
    Join Date
    Nov 2007
    Location
    IL
    Posts
    468
    +1
    17
    Quote Originally Posted by aerow27 View Post
    Thanks for the response
    Do you think the compression would really be a factor since it runs great on the top end?
    Just needs an extra shot of fuel to get there
    I put new needle and spring in that came in the kit.
    After more research it sounds like I should of left the old ones since my pop off pressmight be different now
    It will be about a week and a half before I'm back to the lake to check it out
    Just want to have an idea on what to bring for testing
    Few things...

    No genuine rebuild kit comes with a needle. What kit did you use?

    Compression is close to the "100psi or less=time to rebuild" mark...but not low enough to cause what you are seeing. These were only in the 125-130 range from the factory. They aren't like the seadoos that were more in the 140-150 range.

    You are running lean and therefore pumping the primer is supplying enough fuel to make it run correctly. Sounds to me like its a issue with the rebuild. Need to check pop-off and need to verify kits were installed properly.

  7. #7
    Not sure in the kit brand
    The guy I bought it from gave to me with the purchase

  8. #8
    dannyual777's Avatar
    Join Date
    Jun 2008
    Location
    Lake Conroe (Montgomery,) Texas
    Posts
    760
    +1
    34
    Using genuine Mikuni rebuild kits is an absolute must. They're not cheap. It's going to set you back about $150 for three of these kits.


    Read post #23 in the following link. The small ports that I talk about in that post are extremely important to get cleanly off the line and transition to the mid to upper rpm range.

    http://greenhulk.net/forums/showthread.php?t=287700

  9. #9
    Thanks, I'll order some new rebuild kits

Thread Information

Users Browsing this Thread

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

Similar Threads

  1. 97 GP1200 electrical issue
    By Lilo1899 in forum Yamaha PWC Performance (2-stroke)
    Replies: 0
    Last Post: 07-20-2020, 11:40 AM
  2. 97 gp1200 issue
    By lsx5.3 in forum Yamaha Old School Skis
    Replies: 33
    Last Post: 01-29-2017, 05:25 PM
  3. 1997 GP1200 Fuel Primer installation issue
    By BarkingSpyder in forum Yamaha Old School Skis
    Replies: 5
    Last Post: 08-11-2014, 06:48 AM
  4. 01 GP1200 Got Rid of Fuel Selector Switch - Fuel Tank Pressure Worries
    By pizbrewin in forum Yamaha PWC Performance (2-stroke)
    Replies: 3
    Last Post: 06-15-2012, 12:53 PM
  5. Fuel issue in 2002 GP1200
    By Hamme001 in forum Yamaha PWC Performance (2-stroke)
    Replies: 2
    Last Post: 04-04-2011, 06:15 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
  •