fbpx
Login

 

Jump to Forum..

Oil increasing in oil tank Rotax 912ULS

in General Tech Discussion 9 years ago

  • Re: Oil increasing in oil tank Rotax 912ULS

    by » 9 years ago

    Good reality check Alan.
    Not sure if this has been mentioned in this string; the fuel pump is another likely cause of a fuel in-the-oil problem.
    If the pump shaft seal and the diaphragm break down the fuel has a path to the inside of the gearbox. This is more likely if the fuel pump is very old.

    Pumpcut-away.jpg (You do not have access to download this file.)
      
    Report

  • Re: Oil increasing in oil tank Rotax 912ULS

    by » 9 years ago

    Rob,
    Are you sure the source can be from the fuel pump? I thought all the pumps have a drain between the diaphragm & the shaft seal. If the diaphragm is damaged fuel will come out of the drain, likewise if the shaft seal is leaking the oil will come out the drain.
    Both the crankcase & fuel supply are at positive pressure so any fluid leaks will naturally come out the drain on the pump.
      
    Report

  • Re: Oil increasing in oil tank Rotax 912ULS

    by » 9 years ago

    for sure, we had a couple of situations where the fuel was coming from the pump. That was on the old Pierburg pumps though; it had weep holes, but no low point drain like the new corona pump.
      
    Report

  • Re: Oil increasing in oil tank Rotax 912ULS

    by » 9 years ago

    Send an oil sample in for testing. That will remove any doubt.

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

      
    Report

  • Re: Oil increasing in oil tank Rotax 912ULS

    by » 9 years ago

    Hi Roger,
    Not from fuel pump, cant get in from there, vent holes between diaphragm and gear box.
    I did a very scientific test, poured equal amounts of two samples on concrete in the sun, one evaporated away quickly and left no trace, the other evaporated slower and left a stain, which eventually disappeared.
    My supplier has pumped out the fuel tank and a fresh drop has been made. They have sent samples in for testing, will be interesting to see what the outcome is, diesel I suspect. As you mentioned.
    Cheers.
      
    Report
You do not have permissions to reply to this topic.
Related Topics
Title Category Replies
Belly Oil 912 / 914 Technical Questions 8
Rotax 916 Smoke System 916iS Technical Questions 1
What material is the oil tank lid made of? 912 / 914 Technical Questions 6
Oil line plug caps General Tech Discussion 5
Oil Temperature 912 / 914 Technical Questions 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