Leaning for taxi

Jay Honeck wrote:

What do folks think of this procedure? Can it harm the engine? It's a
Lycoming O320-D2G in a Skyhawk. Thanks in advance.

Can you get the autogas STC for that engine?

We had the O320 in our Warrior, and unleaded autogas completely eliminated
failed mag checks, and the need to lean over-aggressively.

No, the D2G engine is higher compression and requires 100 octane. The
upside is you get 10 more horses (160 vs 150).

Maybe just as well to not mess with autogas out here anyway. Flying in
the nearby mountains can require climbing to 13,000 feet or higher, and
I've heard auto gas is more prone to vapor lock at high altitudes. I'm
no expert though, and haven't done any further research since it's a
moot point for my plane anyway.

Jim Rosinski
N3825Q

"Bob Gardner" wrote in message ...
"Full rich for taxi" is an anachronism. Always lean for taxi.

The test pilot for Mooney said the lawyers made them put that on the
checklist because they were afraid someone would forget and take off
with the mixture leaned. However, if you lean properly, you could
never get anywhere near takeoff power when leaned. I lean so that
additional throttle does not cause any increase in RPM. It took me 3
plug cleanings to figure this out. I've now never had a plug cleaned
outside of annual.
-Robert

Maybe just as well to not mess with autogas out here anyway. Flying in the
nearby mountains can require climbing to 13,000 feet or higher, and I've
heard auto gas is more prone to vapor lock at high altitudes. I'm no
expert though, and haven't done any further research since it's a moot
point for my plane anyway.

Wow -- you climb a Warrior to 13,000 feet?

I never took mine higher than 11.5 -- and THAT was in the winter. And it
took forever to get there.

In the summer, even the longest journey would be over before I reached 8,500
feet...
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

"Jay Honeck" wrote
Wow -- you climb a Warrior to 13,000 feet?

I never took mine higher than 11.5 -- and THAT was in the winter. And it
took forever to get there.

In the summer, even the longest journey would be over before I reached
8,500
feet...
--
Jay Honeck

Think JATO, Jay, JATO!!!!!
--
Jim in NC


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Jay Honeck wrote:

Wow -- you climb a Warrior to 13,000 feet?

I never took mine higher than 11.5 -- and THAT was in the winter. And it
took forever to get there.

In the summer, even the longest journey would be over before I reached 8,500
feet...

Nope--Skyhawk. In addition to the 160 hp engine it's got a powerflow
exhaust. As a guess I'd say that brings the available sea level horses
to something like 170 or 175. It makes a big difference.

Jim Rosinski
N3825Q

On Mon, 06 Sep 2004 00:36:11 GMT, tony roberts
wrote:

Agreed.

The only time the mixture goes forward is when I pull out on the
runway for takeoff, and on short (SHORT) final (in preparation for
a go-around). This is in a '54 C-170B (C-145-2).

You can't hurt these engines by aggressive leaning at low power
settings (worse thing that can happen is you'll put the fire out and
she'll quit).

Bela P. Havasreti

What do folks think of this procedure? Can it harm the engine? It's a
Lycoming O320-D2G in a Skyhawk. Thanks in advance.

Hi Jim
I always aggressively lean my 0300D while taxiing.
At those RPM's you will not overheat the engine.
Check threads on this in the Cessnaa Owners Group.

Tony

On Sun, 05 Sep 2004 23:05:18 -0600, Scott D. wrote:

I do the same thing at sea level (only push the mixture in
1/2 an inch or so to start it, I start it lean and it stays lean until
I pull out onto the runway for take off).

Bela P. Havasreti

On 5 Sep 2004 16:46:24 -0700, (Jim Rosinski) wrote:

What do folks think of this procedure? Can it harm the engine? It's a
Lycoming O320-D2G in a Skyhawk. Thanks in advance.

Jim Rosinski
N3825Q

Here are COS (elv 6100), we don't even start the engine at full rich.
We keep it about an inch out when we crank up on the 172's. Then I
even lean it a little more for the taxi. then I perform the run up and
lean as recommended. I have yet seen a fouled plug on run up doing
this in over 2 years.

Scott D,

I have always started up my 182C 0-470 about 1" from full rich.
Then, always lean to taxi.
And, I lean at full power during run up. None of this girly man 1700
rpm stuff.

Alan Bloom
Dogs can fly.
http://www.flyingmutts.com




On 5 Sep 2004 16:46:24 -0700, (Jim Rosinski) wrote:

Earlier this summer I had a problem with a 400 rpm or so mag drop
during runup. Leaning aggressively at 2100 rpm solved the problem, but
it recurred on numerous occasions. I tried leaning aggressively during
all taxi operations, to the point that the engine would barely run,
and that seems to have solved the problem. No unacceptable mag drop
now for the past month. And a lower throttle setting can be used to
achieve the same taxi rpm as in the past, where the leaning procedure
was "pull the mixture out an inch or so from full rich" (my home base,
2V2, is just over 5000 feet elevation). But I still use the same "lean
to peak rpm then enrichen slightly" pre-takeoff procedure as I always
have at this altitude.

What do folks think of this procedure? Can it harm the engine? It's a
Lycoming O320-D2G in a Skyhawk. Thanks in advance.

Jim Rosinski
N3825Q

If you forget to go to full rich for takeoff, the engine should quit (or at
least complain) when takeoff power is applied. I agree with "the lawyers
made me do it."

Bob

"Robert M. Gary" wrote in message
om...
"Bob Gardner" wrote in message
...
"Full rich for taxi" is an anachronism. Always lean for taxi.

The test pilot for Mooney said the lawyers made them put that on the
checklist because they were afraid someone would forget and take off
with the mixture leaned. However, if you lean properly, you could
never get anywhere near takeoff power when leaned. I lean so that
additional throttle does not cause any increase in RPM. It took me 3
plug cleanings to figure this out. I've now never had a plug cleaned
outside of annual.
-Robert

"Jim Rosinski" wrote in message
om...
Earlier this summer I had a problem with a 400 rpm or so mag drop
during runup. Leaning aggressively at 2100 rpm solved the problem, but
it recurred on numerous occasions. I tried leaning aggressively during
all taxi operations, to the point that the engine would barely run,
and that seems to have solved the problem. No unacceptable mag drop
now for the past month. And a lower throttle setting can be used to
achieve the same taxi rpm as in the past, where the leaning procedure
was "pull the mixture out an inch or so from full rich" (my home base,
2V2, is just over 5000 feet elevation). But I still use the same "lean
to peak rpm then enrichen slightly" pre-takeoff procedure as I always
have at this altitude.

What do folks think of this procedure? Can it harm the engine? It's a
Lycoming O320-D2G in a Skyhawk. Thanks in advance.

I lean for taxi, but I did learn one lesson. On one occasion soon after I
started the practice, the engine quit when I applied power to get the wheels
rolling. The passenger wasn't impressed. Now I lean a little less.

-- David Brooks