fbpx
Login

 

Jump to Forum..

ENGINE OIL INCREASING ABOVE MAX

in General Tech Discussion 13 years ago
hello everybody,
My Rotax 912 ULS from about 30 hours increases the engine oil level (above the MAX level). My Rotax Qualified dealer told me the the engine oil smells of gasoline fuel. he has replaced the 2 carburetors, fuel pump installed is the latest version, despite these the problem is not solved.
Suggestions?
I forgot, the engine parameters are perfect.
Thank you in advance.
Leonardo.

  • Re: ENGINE OIL INCREASING ABOVE MAX

    by » 13 years ago

    Leonardo,

    All other parameters being normal, I would strongly suspect the fuel pump. It is the only point where liquid fuel could leak into the oil system due to a mechanical failure. Do you have any fuel coming out of the fuel pump drain? Is your fuel tank located higher than the engine? Have you changed the fuel pump?

    Bill.
      
    Report

  • Re: ENGINE OIL INCREASING ABOVE MAX

    by » 13 years ago

    hi Bill,
    first of all many thanks for your reply.

    1. during the maintenance check no fuel coming out from the drain has been found, anyway a new one has been installed,
    2. The plane in an Evektor Eurostar, fuel tank, more less, at the same height of fuel pump
    3. yes, as i said, a new one has been installed

    Then, i ordered a fuel test analysis and the result is that the gasoline is a "low standard" RON 95 fuel, "low" because few parts of diesel contamination has been founded, but.....every supplier here in italy has its own standard....big mess
    Now, preventive, i will change the engine oil every 50 hours but the problem is far to be solved.

    Please let me inform if any other suggestions will come up.
    thanks
    Leonardo
      
    Report

  • Re: ENGINE OIL INCREASING ABOVE MAX

    by » 13 years ago

    Hi Leonardo,

    I have seen this happen a few times and I'm not sure what causes it, but on each plane it happened to it went away on its own. It did not persist over time. I would just do my oil changes and get them tested a few times in a row and if there is some fuel it will show up. You should also be able to compare each test to see how much or at what levels the fuel is in the oil. You are better off using the 50 hr. oil change bench mark for your normal changes with auto fuel and 25 for 100LL.

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

      
    Report

  • Re: ENGINE OIL INCREASING ABOVE MAX

    by » 13 years ago

    thanks Roger ! ......in fact, like you wrote, the thing that drive me crazy is not understanding the real cause.
    If something new raises i'll let you know.
    Ciao,
    Leonardo
    www.gardaeagle.it
      
    Report

  • Re: ENGINE OIL INCREASING ABOVE MAX

    by » 13 years ago

    Leonardo,
    We has seen this problem a few times.
    We have found 2 probable reasons.

    Carb allowing fuel past the needle valve when the aircraft is parked (only applies to aircraft with high fuel tanks so not applicable to you).

    Or when the owner has had a trace of diesel in the fuel. We are not sure why but it appears to affect the piston ring sealing & increase the blow by. The blow by gasses contain fuel vapour which condense in the oil. Following our experience we warn about using petrol cans for different fuels on our training courses.
    The problem is likely to resolve itself if you use fuel that is not contaminated, but for now you are going to have to replace the oil more frequently.
      
    Report
You do not have permissions to reply to this topic.
Related Topics
Title Category Replies
Air Ingress at Oil Change 912 / 914 Technical Questions 1
New SB related to various engine issues 912 / 914 Technical Questions 6
Belly Oil 912 / 914 Technical Questions 7
What material is the oil tank lid made of? 912 / 914 Technical Questions 6
Oil line plug caps General Tech Discussion 5
Follow Us

Recent Videos

Safety First!

 

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

Prize Giveaway!


SUBSCRIBE NOW
to automatically enter this years draw!

Login