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  1. #1

    650 WaveRunner will not start without starting fluid


    I recently picked up a 91 650 WaveRunner for $100, put a new CDI in it, but cannot get it to start after being off for more than a few minute without shooting some starting fluid into the carb.

    When I check the vacuum line from the intake manifold to the pump on the carb, while cranking the engine it is under pressure not vacuum. I pulled the carb, opened up the pump and cleaned everything, pulled the manifold, cleaned the reeds with carb cleaner, they all appear to be sealing and the seats look good. Replaced all the gaskets and same issue.

    Once the engine is running I have vacuum on the vacuum line, with the new CDI and have tuning the carb a bit the unit seems to run good, however, if I shut it down, its a bit hard to start, almost immediately after running, and impossible without starting fluid when shut down for more than a few minutes.

    I am assuming that No vacuum on the vacuum line at cranking pressures is the root of the problem, any idea what else to check/replace?


  2. #2
    vomitspot's Avatar
    Join Date
    Apr 2006
    mobile alabama
    you need to open the other side of the carb
    there is a round diapham that is prob hard and needs to be replaced
    the diapham is aroung $20 i think or you can get a carb rebuild kit for like 45
    it should also have the fuel pump diaphams in there as well

    since you had the manifold off how were the reeds?

    the "vacume" sucks and blows
    starting fluid is very bad for the pistons as it washes off the oil that lubs them
    best of luck

  3. #3
    Thanks for the info VomitSpot, when you say the other side of the carb, are you speaking of the side closest to the engine, which has the round disk with the metal insert in the middle?

    If so I will open it back up and replace that as well as the gaskets on the other side. They looked "ok" no tears or gashes so I just cleaned them up since I was unsure if I had a more major problem inside the engine and both those gaskets/diaphrams where on the $20 each.

    All of the reeds looked like they where sealing and the rubber seats looked ok.

    Thanks for the info on the ether, I knew it was not the best, but just wanted to see if this thing worked at all


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