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Hello again,

after eight months of modifying my Europa classic with 912S I am back in the air again.
My flight inspector said after he test flew the aircraft: "funny aircraft but be careful with your payload, it is absolutely not overpowered!"
Well, I thought that impression you will get when you are used to turboprops, like he is.
But today it was me who made the same painful experience.
It is not so easy to realize the lack of with a CS prop but my europa now climbs solo as before with passenger and it seams the have all shortened the runways.
After my last flight today I opened the cowling after half an hour on ground and even the top of the carbs have been that hot you could not leave your hand on them.
Now it is clear for me: I need a stopcock to use the hot water only when needed.
But I wonder if it is only the heat that is responsible for the lack of power
or also the longer suction tube ( don't know the right English term).
Has anybody made similar experiences.
Tomorrow I have my test flight with the flight instructor but I will not let him in before I have got it fixed.

Thank you

Juergen
  • Re: less power with water heated carb heaters?

    by » 12 years ago


    Your carb water heating system should not be a power loss for you. Carbs can and do get hot under a tight cowl. Mine get hot to the touch. I would look at some other cause for a power loss before I pointed a finger at the carb water heating. Fuel reduction and poor prop setup are common causes.

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


  • Re: less power with water heated carb heaters?

    by » 12 years ago


    My carb water heating system does have a cutoff valve but I almost always leave it open. I found that it really didn't affect the engine RPMs at all. My carbs are hot to the touch like yours but when I feel the intake manifold, it's just as cool as without carb heat. My own theory is that the hot carb keeps ice from forming in the carb but the airflow through the carb is so great that the air itself doesn't have time to warm up. Ergo, no RPM drop or power loss.

  • Re: less power with water heated carb heaters?

    by » 12 years ago


    Thank you bouth for your comment.
    I think you are right, many other users of this system share your experiences.
    I also installed a 4 channel EGT meter and even with well balenced carbs depending on the
    powersetting there will be no equality. It differs a bit but with no regular pattern.
    The next thing is hat the EGT meter never shows more than 760°C.
    As the EGT meter is all new for me, I am not shure how to read this.
    I suspect the engine running to lean.
    What do you think?

    Juergen

  • Re: less power with water heated carb heaters?

    by » 12 years ago


    760C is 1400F. That could be a very normal reading. Some of that may depend on field elevations, altitude when looking at the gauge, air intake setup and to a tiny amount the OAT if it is extremely cold or hot. Even the type of fuel could have a tiny influence. One big influence is where the EGT probes are placed. Too far away from the exhaust port and the EGT's will be cooler and too close they will be a little hotter. It may also be a combination of all of these. You may be perfectly okay with these temps. If you want to know for sure then you need to rule in or out each item above.

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


  • Re: less power with water heated carb heaters?

    by » 12 years ago


    1400F is not bad. The leaner and hotter you can run your engine without exceeding the recommended max temp, the better fuel economy you will realize. If I understand you correctly, you have EGT probes on all four cylinders? If this is the case, you will never get all four to read the same. It isn't a problem; its just the nature of the beast. Differences in the internal shape and smoothness of the intake manifold can cause small EGT differences between the front and back cylinders. Left and right side differences can be adjusted with carb adjusting. Front to back differences on a given side will be slight but can't be adjusted out since they both receive air from the same carb.

    Bill.

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