fbpx

 

Hello
I started these days a 912 ul on my new coyote rans.
everything goes well except a cylinder head temperature.
the cylinder sensor n 3 (rear) indicates normal temperatures (80-90degress after 3 minutes, steady rise);
the cylinder n2 (front) rises up to 120 degrees then lowers to 100 then goes back to 120 then lowers to 100, etc;
is it normal, it is a use between 1800 and 3000 rpm and on the ground.
thank you in advance
philippe
bordeaux, france
  • Re: cylinder head temperatures

    by » 7 years ago


    The Cylinder head temperatures should be the same value or very close from cylinder to cylinder.

    It seems like you might have a connection or wiring problem on the fluctuating cylinder and sensor.

    Is the coolant system topped up , right full of coolant ?

    what year of engine ? Do you have the old style heads that the sensor monitors the metal CHT or the new style heads where the sensor is actually monitoring coolant tempature.

    It's possibly, but kind of unlikely, that it is a bad sensor, you could swap the sensors and see if the problem follows the sensor.

  • Re: cylinder head temperatures

    by » 7 years ago


    Salut Philippe,
    This sounds like a poor connection. You may need to make a better contact at the spade connector on the sensor, possibly a bad wire into that spade connector, a bad connection at the instrument or a poor ground. Just go over the connections really well.

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


  • Re: cylinder head temperatures

    by » 7 years ago


    thanks for your quick replies;
    I now know that the temperature difference is not normal and that it is probably a connection or sensor problem
    the engine is new (bought a year ago),it is its second boot after instalation ! so,I want to try not to break it... :dry: : it is with the new style heads where the sensor is monitoring coolant temperature.
    the cooling system seems to be completely filled , difficult to know ...
    I will also check the connections and groung
    I will remove the sensor tomorrow and send it to the vendor for verification and buy another if it is bad;
    I will write you the result, thank you
    philippe

  • Re: cylinder head temperatures

    by » 7 years ago


    first, I will swap tomorrow the 2 sensors,I will understand the problem.
    is there anything particular to know for this disassembly and reassembly?

  • Re: cylinder head temperatures

    by » 7 years ago


    Just swap the two wires. Leave the sensors in place. If the problem stays on the same side it's the sensor and if it changes sides it's the wires.
    The sensors are rarely bad. I put my money on the wires.

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


You do not have permissions to reply to this topic.