Declared first emergency last week

On Sep 8, 10:42*pm, EventHorizon wrote:
There have been a lot of other interesting ideas my post generated:

1 - switch to one mag
2 - carb heat
3 - pulse mags on/off (but if prop stops windmilling you'll need to
restart, not good)
4 - mixture (which is what we did)

Any engine experts have a recommendation on which approach would be best?
Or a combination?

Event Horizon

a wrote in news:a0945182-fc81-4f28-81f3-
:



I remember watching WW1 airplanes flying at Old Rhinbeck (sp?) airport
in NY. Those had two engine settings -- full on or off, and power was
controlled by what an electical engineer might call pulse width
modulation -- switch the mags on and off as needed. I have no idea how
that would work in today's engines, but my instinct would have been to
reach for mags, not mixture. Your way worked, I'll remember that.

Not bein' a pilot (I just jump out of them), doesn't lean cause an EGT
rise? Isn't there some risk of overheating a valve or somesuch if you
take it too lean?

In article ,
Richard wrote:

Not bein' a pilot (I just jump out of them), doesn't lean cause an EGT
rise? Isn't there some risk of overheating a valve or somesuch if you
take it too lean?

You are describing 'not lean enough' aka rich of peak temps, or at
peak temps. Lean the mixture some more and things get cooler.

John
--
John Clear - http://www.clear-prop.org/

Richard schreef:

Not bein' a pilot (I just jump out of them), doesn't lean cause an EGT
rise? Isn't there some risk of overheating a valve or somesuch if you
take it too lean?

Leaning does cause a rise in EGT - up to a certain point, which is the
point we want because it means optimal combustion, thus minimum fuel
burn for the HP. Leaning any further will make the engine very
inefficient, even to the point where it stops.

On a sidenote, many engines (especially the US-type aircooled boxers)
rely on a bit of excess fuel for valve lubrication so we get recommended
to keep them on the rich side of the EGT peak.

On Sep 9, 11:20*am, jan olieslagers
wrote:
Richard schreef:



Not bein' a pilot (I just jump out of them), doesn't lean cause an EGT
rise? *Isn't there some risk of overheating a valve or somesuch if you
take it too lean?

Leaning does cause a rise in EGT - up to a certain point, which is the
point we want because it means optimal combustion, thus minimum fuel
burn for the HP. Leaning any further will make the engine very
inefficient, even to the point where it stops.

On a sidenote, many engines (especially the US-type aircooled boxers)
rely on a bit of excess fuel for valve lubrication so we get recommended
to keep them on the rich side of the EGT peak.

Thank you both for the information.

"jan olieslagers" wrote in message
...
Richard schreef:

Not bein' a pilot (I just jump out of them), doesn't lean cause an EGT
rise? Isn't there some risk of overheating a valve or somesuch if you
take it too lean?

Leaning does cause a rise in EGT - up to a certain point, which is the
point we want because it means optimal combustion, thus minimum fuel burn
for the HP. Leaning any further will make the engine very inefficient,
even to the point where it stops.

On a sidenote, many engines (especially the US-type aircooled boxers) rely
on a bit of excess fuel for valve lubrication so we get recommended to
keep them on the rich side of the EGT peak.

With the correct type of injectors (on injector equipped engines) they can
be leaned far past where lean valve lubrication is a problem. Without the
correct induction system, many engines will run too rough to allow leaning
into safe areas of lean operation.
--
Jim in NC