fbpx
Login

 

Jump to Forum..

Rotax 912ULS shakes alot at start

in 912 / 914 Technical Questions 11 years ago

  • Re: Rotax 912ULS shakes alot at start

    by » 11 years ago

    I had trouble with kickback and rough starts. I changed to the soft start CDI units and it was slightly better. I have a superstition that I might have been flooding half of the engine while turning the propeller to purge the oil from the crankcase. I now advance the throttle when pulling the propeller through. I have not seen a rough start in the last 20 flights.
      
    Report

  • Re: Rotax 912ULS shakes alot at start

    by » 11 years ago

    I fly a 912s on a DTA Trike in Africa since 2003, previously I had a 912 (80hp) mounted. The 912s shakes more at low RPM, I too advance throttle on startup to keep it running smoothly. To the "shaking at 50% throttle" : I only had that when iced (in flight).
    Once though, I hadn't used the motor for 6 months and it gave me more of those shaking issues (shaking to 3500rpm,it was stored in warm/moist climate). there was a layer of rust on the iron core of the magnetos. Using a fine sandpaper did away with that and shaking was instantly better, but not as it should be. but after another 1-2hrs flying it was gone, and i hadn't noticed it again.
    rgds
    Stefan
      
    Report

  • Re: Rotax 912ULS shakes alot at start

    by » 10 years ago

    Shoaib,

    Did you ever solve your problem? Can you please share?

    Andre'
      
    Report

  • Re: Rotax 912ULS shakes alot at start

    by » 10 years ago

    I have also had that problem with violent shakings and it occurs most often in cold weather starts. I believe it has something to do with the fuel system. My solution has been to preheat the motor in cold weather.

    Also i think i should install a complementary electric fuel pump to use at starts. Does anyone know if that is a good idea?
      
    Report

  • Re: Rotax 912ULS shakes alot at start

    by » 10 years ago

    This shaking can be several things. It could be bad engine mounts, poor carb setup, poor starting technique. Choke or throttle position error at start, carb sync out. these are common cause and should be ruled out, but other influences maybe at play, but best to rule out the quick, common and easy ones first.

    Roger Lee
    LSRM-A & Rotax Instructor & Rotax IRC
    Tucson, AZ Ryan Airfield (KRYN)
    520-349-7056 Cell

      
    Report
You do not have permissions to reply to this topic.
Related Topics
Title Category Replies
Age of rotax General Tech Discussion 2
WTB Rotax Backpack Rotax-Owner Community 2
Rotax 916 General Tech Discussion 2
RPM issue, first start, new engine 912 / 914 Technical Questions 8
Roger Lee 912uls 912 / 914 Technical Questions 17
Follow Us

Recent Videos

Safety First!

 

To receive critical-to-safety information on your ROTAX Engine, please subscribe to
ROTAX-OWNER.COM

ROTALK News



ROTALK NEWS Episode 5
Rotax-powered Sling aircraft from The Aircraft Factory, the AVMAP Navigation and engine monitoring system, and the Rotax powered Tucano Experimental and Light-Sport Aircraft.



ROTALK NEWS Episode 4
ROTAX's 915iS-powered Aquila A211 test aircraft, the Scheibe SF-25C Falke (first-ever 912-equipped aircraft!) and ROTAX factory in Gunskirchen, Austria.


ROTALK NEWS Episode 3
Michael Smith's Rotax-Powered Searey Circumnavigation, the amazing Rotax-Powered Lockwood Aircam and Anthony Caere's chimpanzee rescue operations.

Prize Giveaway!


SUBSCRIBE NOW
to automatically enter this years draw!

Login