'Hot' cylinder after overhaul?

[Tony Cox]

Since a major overhaul about 60 tach hours ago now,
I've noticed my #3 cylinder (O470R, 182) is running
consistently hot. It is typically 30-40 degrees warmer than
the average, which puts it at 4-bars in the EDM700
display. To keep this cylinder temp down, I'm having to
leave the cowl flaps open in cruise, which slows me down
some 6knots or so. EGT's are all equal.

Does this indicate extra friction in that cylinder which could
be a problem? The engine as a whole is using about 1qt
every 15 hours or so now & I followed the Continental
break-in procedure to the letter. It's running great.

Did someone miss a bit of baffling in reassembly? Can
missing baffle really make that much difference?

Perhaps things will return to normal after a few more hours
and I should stop worrying. Comments?

--
Dr. Tony Cox
Citrus Controls Inc.
e-mail:
http://CitrusControls.com/

[Scott Skylane]

Tony Cox wrote:
> Since a major overhaul about 60 tach hours ago now,
> I've noticed my #3 cylinder (O470R, 182) is running
> consistently hot. It is typically 30-40 degrees warmer than
> the average, which puts it at 4-bars in the EDM700
> display. /snip/

Tony,

Baffling certainly could be the issue here, make sure the flexible
baffle seal in this area is laying down correctly. Also, you may want
to swap CHT probes with another cylinder, and see if the indication
follows the probe. Also check if this jug has the factory CHT probe in
it, in which case the sparkplug gasket probe for the EDM *will* read
differently than the others. Good luck, and

Happy Flying!
Scott Skylane
N92054

[Jim Vadek]

How hot is the CHT reading?

"Tony Cox" > wrote in message
thlink.net...
> Since a major overhaul about 60 tach hours ago now,
> I've noticed my #3 cylinder (O470R, 182) is running
> consistently hot. It is typically 30-40 degrees warmer than
> the average, which puts it at 4-bars in the EDM700
> display. To keep this cylinder temp down, I'm having to
> leave the cowl flaps open in cruise, which slows me down
> some 6knots or so. EGT's are all equal.
>
> Does this indicate extra friction in that cylinder which could
> be a problem? The engine as a whole is using about 1qt
> every 15 hours or so now & I followed the Continental
> break-in procedure to the letter. It's running great.
>
> Did someone miss a bit of baffling in reassembly? Can
> missing baffle really make that much difference?
>
> Perhaps things will return to normal after a few more hours
> and I should stop worrying. Comments?
>
> --
> Dr. Tony Cox
> Citrus Controls Inc.
> e-mail:
> http://CitrusControls.com/
>
>

[Tony Cox]

"Jim Vadek" > wrote in message
news:aABXa.65943$Ho3.9080@sccrnsc03...
> How hot is the CHT reading?
>

I can keep the hot cylinder down to around 375 with
the cowl flaps almost fully open, at around 5000' here
in the desert southwest. The rest hover around 340.

--
Dr. Tony Cox
Citrus Controls Inc.
e-mail:
http://CitrusControls.com/

[Tony Cox]

"Sydney Hoeltzli" > wrote in message
...
>
> It's also possible it might be a sign of problems (exhaust
> valve not seated quite right? what say the engine gurus?)
> but let's hope for something simple.
>

Compressions are all 73+-1 /80. I'll rechekd the baffling...

Ta!

--
Dr. Tony Cox
Citrus Controls Inc.
e-mail:
http://CitrusControls.com/

[Jim Weir]

Roughly...temperatures are worth the coin. That is, a dime size hole in the
baffling will cause 10° rise, a quarter 25°, and so on up to the 50°
half-dollar.

Jim


"Tony Cox" >
shared these priceless pearls of wisdom:


->
->Did someone miss a bit of baffling in reassembly? Can
->missing baffle really make that much difference?

Jim Weir (A&P/IA, CFI, & other good alphabet soup)
VP Eng RST Pres. Cyberchapter EAA Tech. Counselor
http://www.rst-engr.com

[Tony Cox]

"Jim Weir" > wrote in message
...
> Roughly...temperatures are worth the coin. That is, a dime size hole in
the
> baffling will cause 10° rise, a quarter 25°, and so on up to the 50°
> half-dollar.
>

Interesting rule of thumb. But how come I'm only seeing an increase
in the middle cylinder on the passenger side?

[gross_arrow]

is this by any chance the cylinder on which the stock cht probe
is installed? in my installation, (t-arrow iii), the stc on the
edm-700 required that the stock cht be retained (it's #1 on the
tsio-360fbfc). so on that cylinder, instead of a bayonet probe,
the edm-700 uses a "gasket" probe under the spark plug. the
gasket probes are notorious for reading high -- on my t-arrow,
#1 reads about 50 deg higher than the hottest of the other 5
cylinders. we've replaced the gasket probe to no avail. when
the jpi flags a warning in climb (470 degrees), the stock cht
still shows a good 16th or 3-32nds of an inch below the red line.
our a & p has checked the temps and found the gasket probe to
read high. so, at least in our case, it is a "false alarm".
don't know if the same is true for you, but you might want to
check it out.

g_a




"Tony Cox" > wrote in message k.net>...
> Since a major overhaul about 60 tach hours ago now,
> I've noticed my #3 cylinder (O470R, 182) is running
> consistently hot. It is typically 30-40 degrees warmer than
> the average, which puts it at 4-bars in the EDM700
> display. To keep this cylinder temp down, I'm having to
> leave the cowl flaps open in cruise, which slows me down
> some 6knots or so. EGT's are all equal.
>
> Does this indicate extra friction in that cylinder which could
> be a problem? The engine as a whole is using about 1qt
> every 15 hours or so now & I followed the Continental
> break-in procedure to the letter. It's running great.
>
> Did someone miss a bit of baffling in reassembly? Can
> missing baffle really make that much difference?
>
> Perhaps things will return to normal after a few more hours
> and I should stop worrying. Comments?

[Tony Cox]

"gross_arrow" > wrote in message
om...
> is this by any chance the cylinder on which the stock cht probe
> is installed?

Yes, indeed. I checked today and this is exactly what the
problem is. I'll check on availability of the part (5050-A) from
JPI.

--
Dr. Tony Cox
Citrus Controls Inc.
e-mail:
http://CitrusControls.com/