89 evirude 70 hp vro: high rpms?

Discussion in 'Boats and Motors' started by allwayzfishin, Jun 21, 2008.

  1. allwayzfishin

    allwayzfishin just 1 more cast!!!

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    took the boat out fri and started here up with no problems. as i put her in gear i noticed the idle speed was a little fast and she was running at about 1700-2000 rpms. opened her up and as she planed out the engine was at 6000rpms and had a pulsating thrust. lost some power too. not sure where to start on this repair, so i am gonna get a shop manual first before i decide to take it to a repair guy. could this be a simple fix or no? gonna check fuel restrictions then clean out the carbs and check the idle switch. could this be something with the throttle and linkage timing? any suggestions or help would be appreciated... thanks
     
  2. OSU_Fisherman

    OSU_Fisherman Bassin' Buckeye

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    I have an '89 Johnson GT150 that had a problem with losing power after getting on plane. For me, it was all in the fuel delivery.

    I changed the fuel/water seperator, inline fuel filter, Primer bulb and hose assmbly and it didn't fix anything.
    Then, I noticed that the surge hose coming from the VRO had a kink in it.... cut it out and it has run 100% perfectly ever since.

    Go along the entire fuel system and try fixing the little things first. If its starting fine and running fine (with the exception of lost power) then its got to be something little going wrong. I was just about ready to order the VRO rebuild kit before I found that hose.... a $100 fix turned into a 5 minute fix that cost me..... ready for it.... $0.
     

  3. fishingguy

    fishingguy The Inferior Fisherman

    I would find out what the idle rpm and wide open rpm is supposed to be. I am not familiar with that outboard but 1700 rpm at idle sounds high. Someone on here will know. I know my io purrs like a kitten at about 650 rpm at idle, but it's not an outbord.
     
  4. question, did it run perfect the last time you used it? if it did , its most likly a fuel delivery problem .start there .don;t make this a major problem [till all else fails] also take off the vro cap to the tank , see if you can blow air thru it? no air? clean out the cap with gas. and yes 1700 rpm;s is high more like a 1000 would be in the ball park. let us know what you find.
     
  5. NUM1FIRE

    NUM1FIRE FIREFIGHTER/1ST RESPONDER

    89 johnson 70 hp vro has a recommended operateing range of 5000 to 6000 rpms. a repair manual has really helped me out on my 89 johnson 70 hp vro outboard