lml@lancaironline.net Mailing List Archive

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Valve guide is worn - - serial compression checks are in order.

-----Original Message-----
From: beech-owners-bounces@beechcraft.org
[mailto:beech-owners-bounces@beechcraft.org] On Behalf Of Max Hegler
Sent: Saturday, March 27, 2004 10:32 PM
To: beech-owners@beechcraft.org
Subject: B: Fluctuating EGT..

Today I had an unusual EGT indication on the #2 cylinder (IO 520BA). At

cruise, the EGT started rapidly fluctuating 25 to 30 degrees. CHT was
fine
and running about 360. All other EGTs and CHTs were running steady. I
usually monitor #2 cylinder as it is the hottest. Flight was at 9500
ant
10500 with outside temps about 4C in clear conditions. Cruising about
165
KTAS at 40 LOP. I was thinking about switching #2 and #4 probes
tomorrow
and see it the indication follows the probe. Any other suggestions?

----- Original Message -----

From: Cy Galley

To: Lancair Mailing List

Sent: Sunday, March 28, 2004 5:40 AM

Subject: Re: [LML] relative temps?

The point being that even the maximum temperature shown will change relative to altitude and a bunch of the many the other parameters. It changes and is not static, Further since they are self generators, they are not really calibrated. A true system would take into account the cold (meter) junction cabin temperature as well.

----- Original Message -----

From: Gary Rodgers

To: Lancair Mailing List

Sent: Saturday, March 27, 2004 10:40 PM

Subject: [LML] relative temps?

Cy

< Since you are measuring the heat output, anything and every thing that effects engine power will effect the temperature. Probe location, cylinder cooling, ambient air temp, altitude, throttle setting, turbo boost if you have it, engine condition, timing, spark plug condition, air humidity, mag condition, impulse spring condition, exhaust system condition, gasoline. airfilter condition, and I'll bet there are some I have missed. Between cylinders the probe location, valve condition, baffling(cooling), and injectors can and do change the indicated temps for each cylinder.>

Guess I'm confused about your 'relative' reference as well. All the conditions you describe affect the output temp of the cylinder exhaust, but that doesn't mean that the actual recorded/reported temperature isn't the real temperature that must be considered when operating the engine within the temperature tolerance of the components. Or am I missing something?

Gary R