fbpx

 

I have been having a conundrum of starting issues for the last few months. It has become gradually more difficult to start my Rotax 912 ULS. Now when I go to start it sometimes it will not start at all and then I'll go out the next day and it will fire right up. When I cannot start it I always check and there is fuel in the carb bowls and all the plugs look good. If I troubleshoot the modules by heating them up ometimes that will help and other times it doesn't make a difference.

A friend of mine let me borrow a couple of his newer style ignition modules and the plane starts up every time. I went through each module and tried to start it while only having one installed at a time. The newer style modules both started it. One of the older style modules didn't even come close to starting it and the other one was close but also wasn't able to start it. 

Out of curiosity I also tried one of his older style modules that was suspected to be working but it also wasn't able to start it. Is it possible that I have 3 ignition modules that are all bad or can there be another reason that some days it wont start and the next it will work perfectly? My mag checks look good on all of the modules at all RPMS, the battery is fine. 

Any help would be appreciated, thanks.

  • Re: Starting Issues

    by » one month ago


    The only thing I can suggest is check the wiring or pins connecting to modules. Perhaps some contact cleaner on pins. May have a cable short in connection on old style due to vibration. I believe rotax had issue on old style and went to six pin. If fuel is ok than fire is missing. 


  • Re: Starting Issues

    by » one month ago


    Brandan

    Please go through my posting starting two weeks ago. I had a similar issues. I listed the things I did prior to sending my Electronic modules to be bench tested, where they bought failed. New ones fixed my problem. You most likely have one that has failed and one that is failing intermittently. 
    Have you tried starting on left mag and then right mag? Have you checked for spark?

    good luck

     

    Gino Cavicchioli


  • Re: Starting Issues

    by » one month ago


    Don't know what kind of ignition switch you have, key or toggle. Might be going bad. You don't want it grounding while in flight especially both modules. 

    IF toggle switches, bypass and see if it starts all the time if you have push botton start.  If all key you can bypass but more difficult. You have to turn fuel valve off for engine to stop after start. Take extra care when modules hot. 

     

     


  • Re: Starting Issues

    by » one month ago


    I have the six pin setup but I have yet to try to clean the pins. I have checked all of them for security though and they look good. I have an older key start so I can't start one module at a time. Basically I only installed one module at a time to see which ones weren't working without the influence of the second module. 


  • Re: Starting Issues

    by » one month ago


    Looks like you have answered the problem that although expensive you need new modules. But, this coming back next day, ENGINE starting, and all good is an issue. Well, as another member said one old module working sometimes and after engine start all ok with both old modules after start. 

    The only other possibility which I doubt would be a bad key ignition as stated before. If you don't have some kind of back EMF protection either at the starter solenoid or at key ignition like a diod, ultimately spark generated at key ignition would cause it to go bad. 

    Starting procedure inside modules and running after start is different as it relates to hardware and software. I know modules are expansive but you might have to bite the bullet. 

     

     

     

     


You do not have permissions to reply to this topic.