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After takeoff a whistling sound was heard and climb rate deteriorated substantially.

Aircraft is a TL 3000 Sirius 2015 with Garmin G3x panels, engine has 600hrs TT and has an electric CSU prop.

On the ground whistling sound started above 4500 rpm through to max rpm.

Throttle reaches max rpm at about 3/4 travel and 21lph. Further throttle increases rpm decreases, engine sounds rough and fuel flow increases to 26lph.

Suggestions have been whistling sounds like air sucking in (checked but not found). Suggested to apply CRC to gaskets and run engine to check for any dry spots? Rough running suggests plugs. Plugs were changed recently suggestion has been to put old plugs back in to eliminate new plugs as an issue.

 Any other ideas or suggestions appreciated or if anyone has experienced anything similar comments appreciated.

  • Re: Power loss after takeoff

    by » 3 years ago


    Off top of my head, first rule out a propeller control failure problem. Can you lock the propeller in full fine (takeoff) pitch and try a ground run at full power? If the problem is still there it could be an engine problem. If not it is a propeller problem. What are EGT’S doing?


  • Re: Power loss after takeoff

    by » 3 years ago


    Thanks I could not reply yesterday as a new member. The prop has been in full fine, EGT's are pretty normal but have in the past few weeks been high. Further investigation yesterday changing the spark plugs showed carbon on the number 3 cylinder plugs so we are now suspecting a blocked fuel injector in that cyl. We also found a couple of ignition caps were not fully screwed into the leads, fixed but no change found. The CRC idea didn't show any evidence of any leaks but to be fair hard to see. We have got access to a BUDS cable due Monday so we plan to download the ECU data for analysis and see if that helps find the issue, its not clear from the Garmin data in Savvy aviator, screen shot below shows reducing MAP, RPM and ROC in climb during a test circuit yesterday.

     

    Hope this process is useful to others who may have found similar symptoms.

    29840_2_Screen Shot 2021-06-17 at 2.37.29 PM.png (You do not have access to download this file.)

  • Re: Power loss after takeoff

    by » 3 years ago


    Phil Southerden and I spent another day yesterday troubleshooting ahead of receiving the BUDS cable tomorrow. We replaced the pressure regulator and found no significant change although the pressure is lower than another 912is on the field when both are measured through Savvy Aviator.

    Plucking up courage we removed the injectors from the number three cylinder and found when the first injector cable was disconnected the engine ran smoothly but when the rear injector cable was removed it ran very rough.

    Following the maxim:

    The One that does Not produce an Additional error is the Bad One.
    The One that causes a cylinder to fail completely is the one Next to the Bad One!

    We assumed the front injector was faulty, but to prove this we then switched the cables attaching the front injector cable to the rear injector and vv. Now magically the front ran rough and the rear smooth.

    So we think we are closing in on the problem and now suspect its a problem with data coming to the injector meaning likely a sensor input or the computer and we hope that the BUDS cable tomorrow will make things clear. If nothing else we are certainly learning a lot about the engine.


    Thank you said by: RotaxOwner Admin

  • Re: Power loss after takeoff

    by » 3 years ago


    Several months ago we posted a problem with our 912is sport. The engine reached peak RPM around 5200 at about 60% throttle travel with MAP about 29" at the same time and more throttle caused rough running. BUDS diagnostic said lack of air. We finally located the problem, sharing in case others have the same issue and its was a collapsed exhaust baffle restricting exhaust gas and back pressure restricting airflow in. 


    Thank you said by: Bill Hertzel, john gunn, RotaxOwner Admin

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