does intentional dead stick hurt the engine?

[Greg Johnson]

Is it OK to intentionally run an engine out of gas under power?

Will it hurt the engine?

I've been having fun lately working on autos. When gas is starting to
get low at the end of a flight, I climb out and do a practice
auto using the throttle hold switch. Then, I climb out a second time, set
up for an autorotation, and climb at that spot to gain altitude and
wait for the gas to run out and the engine to quit. At that point I
enter one FINAL auto for the flight.

My question is this: Is this bad for the engine? (No, not because of
the possibility of dropping the engine on the ground from 300 feet up,
but because of the possibility of leaning it out, overheating it, etc.)
Just as the heli is running out of gas the engine suddenly speeds up and
gets louder. And then it gets very quiet... ;-)

I assume the engine is leaning out just before it dies. My guess is that
since this happens pretty quickly, there isn't much of a chance to cause
the engine to over-heat etc. Is this true? Or am I damaging the
engine by doing this repeatedly?

(By the way, this is a ringed Thunder Tiger 39 engine.)

Thanks for any thoughts -

Greg

[Beav]

"Greg Johnson" <gregflies1@yahoo.com> wrote in message
news:8faa960.0408201608.c970a7e@posting.google.com ...
> Is it OK to intentionally run an engine out of gas under power?

It is if you can auto.
>
> Will it hurt the engine?

Nope.
>
> I've been having fun lately working on autos. When gas is starting to
> get low at the end of a flight, I climb out and do a practice
> auto using the throttle hold switch. Then, I climb out a second time, set
> up for an autorotation, and climb at that spot to gain altitude and
> wait for the gas to run out and the engine to quit. At that point I
> enter one FINAL auto for the flight.

Beware that "one last" anythng :-))
>
> My question is this: Is this bad for the engine?

No, in fact at the end of a days flying, you SHOUD run the engine out of
fuel andn then start it up agin without re-fuelling. The motor will start,
but not continue running (obviously), but it WILL get a touch hot and this
evaporates all the nasties left in the engine along with methanl based fuel
reidue which is hygroscopic (it attracts water). The result of this is the
engine stays in good condition and the carb isn't full of crap next time you
go out flying.

(No, not because of
> the possibility of dropping the engine on the ground from 300 feet up,
> but because of the possibility of leaning it out, overheating it, etc.)

See above. Heat can be your engines best pal.

> Just as the heli is running out of gas the engine suddenly speeds up and
> gets louder. And then it gets very quiet... ;-)

Loverly:-))

>
> I assume the engine is leaning out just before it dies. My guess is that
> since this happens pretty quickly, there isn't much of a chance to cause
> the engine to over-heat etc. Is this true? Or am I damaging the
> engine by doing this repeatedly?

Not at all. Again, see above.
>
> (By the way, this is a ringed Thunder Tiger 39 engine.)

Well it wouldn't matter if it DID get bollocksed, they cost bugger all
:-))))))


--
Beav


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