My 912 ul engine is 2 yrs old and has 225 hours on it. The oil pressure gauge has alway fluctuated 10-15 psi. I recently discounted the oil pressure sending unit and hooked a gauge directly to the engine. The pressure was fine, no fluctuations. The next step I presume is to test the gauge and sending units. Any other suggestions? Also, is there an easy way to test the gauge and sending unit?
  • Re: Oil pressure gauge fluctuations

    by » 4 months ago


    If the pressure sending unit is engine mounted vibration and heat will damage it.

    https://www.aircraftspruce.com/catalog/inpages/rv12remote05-11919.php?clickkey=6024154

  • Re: Oil pressure gauge fluctuations

    by » 4 months ago


    ... The oil pressure gauge has always fluctuated 10-15 psi.

    By fluctuating, do you mean it varies with throttle changes; Or do you mean it changes up and down more than once a second?
    Is this when the engine is Hot, Cold, Or all the time?
    [quote]
    I recently discounted the oil pressure sending unit and hooked a gauge directly to the engine. The pressure was fine, with no fluctuations. The next step I presume is to test the gauge and sending units. Any other suggestions? Also, is there an easy way to test the gauge and sending unit?[/quote]

    What type of gauge did you hook directly to the engine?
    Was it fine at the same Temperature and RPM that you normally experience the problem?

    The definitive way to test the measuring equipment is to install a "Tee" and monitor both gauges simultaneously.

    The best gauge to use is a purely Mechanical Gauge.
    It will have the fastest response time and reveal any abnormalities.
    Electric gauges of any variety will have difficulty tracking rapidly changing pressures.

    Bill Hertzel
    Rotax 912is
    North Ridgeville, OH, USA
    whertzel1@yahoo.com
    Clicking the "Thank You" is appreciated by all.

  • Re: Oil pressure gauge fluctuations

    by » 4 months ago


    The oil pressure gauge show 10-15 psi swings at cruising setting, 4k rpm. The indicator moves every sec.
    I used a analog gauge directly hooked to the engine and it gave a consistent reading.
    My engine has an electronic sending unit. I assume it is either the sending unit or gauge that is malfunctioning

  • Re: Oil pressure gauge fluctuations

    by » 4 months ago


    My plane is an Air Cam. The engine is mounted on the back of the wing. Its a pusher.
    It's probably 20 ft from the engine to the front panel

You do not have permissions to reply to this topic.