Robin 35 losing power after gets hot.

Discussion in '4-Stroke Engines' started by cncsmyhobby, May 7, 2013.

  1. cncsmyhobby

    cncsmyhobby New Member

    I have about 10 hours on my GEBE with a Robin 35 engine. I need help diagnosing a power loss problem. After about 3-4 miles of pretty hard riding with stops and starts around my residential neighborhood, it loses top end power as if starving for fuel. I have tried different fuels, run it with and without the air filter, disassembled and cleaned out the carburetor, and fuel line filter, replaced the fuel lines. The spark plug looks very clean. I am thinking that I need to check the valve clearance. Any one else have this problem and want to share?
    Cheers, Bill
    :confused:
     

  2. darwin

    darwin Well-Known Member

    Try riding it with just half a tank of fuel, assuming your using OEM tank. Just tighten the fuel cap half way and see if issue goes away, if it does your cap is not venting properly. Half tank is suggested to avoid spillage.
     
    srdavo likes this.
  3. cncsmyhobby

    cncsmyhobby New Member

    Thanks darwin, that was it! The little rubber check valve in the cap was stuck shut and would not allow air into the tank. Makes perfect sense in hindsight.
     
  4. LR Jerry

    LR Jerry Well-Known Member

    Often it a simple fix; be glad when it is.
     
  5. darwin

    darwin Well-Known Member

    Yea with a new soobie I didn't think it was a carb problem.
     
    srdavo likes this.
  6. LR Jerry

    LR Jerry Well-Known Member

    I went and stuck a pin through my vent holes just to make sure they were clear.
     
Loading...