proper engine shutdown and startup

[mikedean]

after several hours of flying today, what is the recommended way for engine shutdown, and then after refueling and lunch, what is the recommended way for engine restart......your advice ????

[Av8r3400]

What engine make/model?

[mikedean]

model lV rotax 912
912 ul 80 hp

[akarmy]

after several hours of flying today, what is the recommended way for engine shutdown, and then after refueling and lunch, what is the recommended way for engine restart......your advice ????

So there must be a hidden question or additional information as to why you ask this question...

because, on a properly working 912, you turn off the key to shutdown and after lunch, turn it to start and it fires on the first blade...

[mikedean]

ok to just shutdown, or increase rpm for a minute or two before shut down
startup after flying for a while and very hot outside....throttle closed when starting, or throttle opened a little....asking this because after flying for a while and hot outside, sometimes takes several trys before engine will start

[akarmy]

I've found it nicer to raise the RPM to about 2500 then as I pull it to slow idle shut it off as the extra speed caries the prop a bit more and seems a bit less abrupt.


startup after flying for a while and very hot outside....throttle closed when starting, or throttle opened a little....asking this because after flying for a while and hot outside, sometimes takes several trys before engine will start

Sounds like a bit of vapor lock in your fuel lines when hot. Some 912 installations have a return line from the fuel T going to the carbs that returns back to the header tank. I think these tend to keep cool fuel running through the fuel pump and may make starting easier.

I just crack the throttle open a bit with no choke when starting hot and it fires every time. Mine does have the return fuel lines.

Hope that helps.

[mikedean]

thank you so much ......

[Av8r3400]

I was told to set the idle to 2000-2100 before shutting down, then the throttle is set for start up.

Remember the "choke" or more properly, the enrichment circuit, does not function if the throttle is above idle.

[Slyfox]

Ah! shut down and startup. I go with a throttle that idles at about 500. WHAT you say. yup. I don't idle it there, I just have it that way so it shuts down nice. PUll the throttle all the way back as you hit the switches, no bang no nothing. On statup I either have the throttle all the way back, if it kicks it needs full back, compression thing. If it's hot, I use half throttle and hit the starter. As it hits I pull slowely the throttle back until a nice idle.

I love the real slow idle, helps on landing, no float. On my 912uls I have a compression thing, my lyc. does it also(will lock when starting). With the throttle all the way back and hit the starter it starts right up, as it does I add throttle until it's running right where I want it. I didn't have the return lines on my 912ul and I don't have them on my 912uls.

[Aaron]

I was doing some research on service bulletins and service letters from Rotax and came across a service letter (SL-912-016 (http://www.rotax-owner.com/SI_TB_INFO/returndoc.asp?PATH=http://www.rotax-owner.com/si_tb_info/serviceletter/sl-912-016.pdf&DOCID=SL-912-016&S_TYPE=SS)) in regards to engine behavior for the 912 & 914 series engines. See sections 3.6 & 3.7 for engine starting and shut down tips.