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  1. #1

    brand new rebuld ,Less top end?????

    hey guys just put a new engine in and still not through the first tank of gas yet. Does anyone know if adding oil to the fuel to help with run in , If it would cause a loss of top end???? im sure i had it to 60 mph before the rebuild . i only got it 2 56 mph the other day


  2. #2
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    What motor is it? Who did the rebuild? I don't think premix would make that much difference. What was the weather like while you were testing it? Weather can have an effect. Sometimes new engines need a little time to develop full power. What was the max RPM with the old motor compared to the new one?

  3. #3

    hey bryan

    mate its a virage tx 1200 carbed. was pretty flat the day i took it out . not to sure on the rpm on old engine around 7000 i guess . had the new one to 7 grand as well. had the engine done here in sydney by a company well known on their rebuilds on boat motors.

  4. #4
    Also bryan ,
    obvisously having oil in the fuel as well well help go through some plugs until this first tank is emptied. but the plug closest to the pump is fecked . while the other 2 just look a little oily. any idea why this one is worse off? nearlly left me stranded the other day

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    Re: brand new rebuld ,Less top end?????

    In general motors won't reach full power until the rings are properly seated. Also, your focus should be on proper break in, not top speed right now

  6. #6
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    Same RPM should get the same top speed on flat water, unless there are jet pump issues.

  7. #7
    Click avatar for tech links/info, donation request K447's Avatar
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    Quote Originally Posted by jasthecase View Post
    ... Virage tx 1200 carbed. was pretty flat the day i took it out .

    not to sure on the rpm on old engine around 7000 i guess . had the new one to 7 grand as well.

    had the engine done here in sydney by a company well known on their rebuilds on boat motors.
    The carburetor 1200 red engines typically turn around 6700RPM at wide open. 7000 is rather high for that engine (if stock porting and compression) and is getting beyond the power band.

    What impeller is in the jet pump and what condition is it? Blade clearance? Stator vane condition?

    Is the ride plate well sealed to the hull and the pump tunnel well sealed to the pump base?

  8. #8
    ok had it back on the water today. it maxed at 6740 and was reading 56.4 on the dream ometer so its still down on top end. so k447 you really know your shit. I just put a new solas i think it 15/21 and wouldnt be more than 5hrs old( when it hit 60 mph it was with this prop in). not sure on stator vane condition . and the ride plate and the pump tunnel look ok .
    got another question . today whilst on it the oil got really really low ( i know,i know i just didnt think it would use so much ). does the ski have some feature that it cuts out when the oil level is really low??

  9. #9
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    6740 RPM is about where is should be. Check your speed with GPS. You may have something affecting display readings, such as a slight clog in the pickup tube.

  10. #10
    thanks bryan. bryan any idea's about that oil question i said in last comment? and where is the pick up tube? sorry for being so stupid, but how does the speedo on these things work? you guys are teaching me alot about this thing.so thanks for your time.

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