Burping the Rotax 912ULS Aircraft Engine: An Owner's Video

H. Paul Shuch is a Light Sport Repairman with Maintenance ratings for airplanes, gliders, weight shift control, and powered parachutes, as well as an independent Rotax Maintenance Technician at the Heavy Maintenance level. He holds a PhD in Air Transportation Engineering from the University of California, and serves as Director of Maintenance for AvSport of Lock Haven.

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designrs
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Re: Burping the Rotax 912ULS Aircraft Engine: New Video

Post by designrs »

I like burping after a flight. It is just easier.
Question… is it ever too early to burp.
Say you shut down and in 5 or 10 minutes you are ready to leave the plane.
Would it be bad to burp the motor when it is still pretty hot after use?
Could you be removing oil from the hot motor too early?
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drdehave
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Re: Burping the Rotax 912ULS Aircraft Engine: New Video

Post by drdehave »

You wait a few minutes, so all the oil up in the engine components, from the recent run, has time to drain back down to the "dry sump," where you can then pump (force it with blow-by pressure past the rings) it back to the oil tank, by turning the prop.

How long is long enough? I don't know exactly; maybe Roger Lee does. I have just settled on 20 minutes, because I know that is plenty of time! Ten minutes (or even less) may work just as well.
When I finish flying for the day, by the time I get the bugs off, fuel it for tomorrow, and fill in my log book--well, that's usually about 20 minutes, right there! So then I burp it; then, I know she'll burp in 5 prop-pulls (usually 1 or 2!) of less, tomorrow morning!

The only "harm" that could come from burping too soon after shut-down would be that not all oil has drained off the engine components, yet. And that's no 'harm' at all...except, it may take longer to burp the next day.
Last edited by drdehave on Tue Sep 23, 2014 9:59 pm, edited 1 time in total.
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designrs
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Re: Burping the Rotax 912ULS Aircraft Engine: New Video

Post by designrs »

Super… thanks!
rgstubbsjr
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Re: Burping the Rotax 912ULS Aircraft Engine: New Video

Post by rgstubbsjr »

Well Done. Thanks for the tips.
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designrs
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Re: Burping the Rotax 912ULS Aircraft Engine: An Owner's Vid

Post by designrs »

Thanks drbehave! I've been burping about 20 minutes after flight with about 15 blade pulls. Then just about 8 blade pulls before flight. Oil level is always exactly the same on the dipstick. This the way to do it for painless burping!
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