I have a Dynamic with Rotax 914 in Brazil for 7 months with 340 hours.

Several times I realized that the takeoff is not getting the 40 ”MAP. When I use to check in solo the TCU (Master ON and IDLE), I notice that Waste Gate is closed and doesn´t move during this check. 

Several times I lubricate with WD40 and it works again for about 15 days and then it locks again.

In the past friends told me that it´s happens because impregnated with lead from Avgas 100LL.

Then, 5 months ago I started to use unleaded gasoline, but nothing has changed. Every 15 days, during check-in I lubricated with WD 40 and move with help of my fingers to release (free moving) the WG.

What should I do?


Thank You

  • Re: Waste Gate locked

    by » 4 weeks ago

    The wastegate shaft has a lot of lead build-up and needs action to clean it out.

    the best way to clean it:

    • Remove muffler (I know, this is fun...but it gives the best access to the W/G shaft, forget about trying to spray uphill into the shaft from the exterior) 
    • With throttle at idle turn master ON, and then OFF as soon as the servo is in the W/G open position.
    • Spray brake-clean or penetrating fluid such as "AeroKroil" or "liquid wrench or "mousemilk") (not WD40) and rotate the W/G lever back and forth until you can feel it is clean and loose.


  • Re: Waste Gate locked

    by » 4 weeks ago

    Thanks Rob, I´ll do this is this weekend and after I´ll make a feedback for you..


    In Brazil we don´t have AeroKroil or Liquid Wrench or Mousemilk, but I´ll try to buy a good spray brake-clean.

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