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CHT readings?

Posted: Sun May 23, 2004 12:05 pm
by danMichael
'All:

Something Ive been curious about... On my F24R (440C-5, 200hp), I
never see CHT readings in flight above 275F. The gasket-type
thermocouple is mounted on the number 1 left spark plug. The gauge
seems to indicate ambient temperature correctly, but Im wondering if it
is accurate at higher temperatures.

What values do you typically see on your Ranger?

:Dan
:NC81323'

Re: CHT readings?

Posted: Sat May 29, 2004 4:46 am
by Airy-Hugues Millet
'Hy!

We currently run around 180 Celsius (don't have translation chart under my
hand), it doesn't move a lot along seasons, and reach nearly 200/205 only
during hottest weather like last summer when having 40celsius air
temperature on ground!!

The thermocouple is assembled on the left spark plug of cylinder no2, which
seams to be the "worst" for heating....(no one being the first on the
firewall side and no six being on the plane front!).

Interesting to make the difference!

And I have a question, what are your Oil temperature and pressure during
cruise along seasons!??
What grade of oil are you using (wer do use AERO100 mineral currently and
120 on hot condition...so almost 80% of flying hours during late spring and
summer......especially on great airports tarmac, like on air force base
where the air is going quickly very hot above such surface!
(last year some planes like ours and aerobatic one did encounter stall at
higher speed as usually during airshow above an army airbase!)


Have fun!


Airy

>From: danMichael
>Reply-To: fairchildclub@yahoogroups.com
>To: Fairchildclub@yahoogroups.com
>Subject: [fairchildclub] CHT readings?
>Date: Sun, 23 May 2004 13:05:22 -0500
>
>All:
>
>Something Ive been curious about... On my F24R (440C-5, 200hp), I
>never see CHT readings in flight above 275F. The gasket-type
>thermocouple is mounted on the number 1 left spark plug. The gauge
>seems to indicate ambient temperature correctly, but Im wondering if it
>is accurate at higher temperatures.
>
>What values do you typically see on your Ranger?
>
>:Dan
>:NC81323
>
_________________________________________________________________
Trouvez l'âme soeur sur MSN Rencontres http://g.msn.fr/FR1000/9551'

Re: CHT readings?

Posted: Mon Aug 02, 2004 2:37 pm
by danMichael
'Airy:

Sorry for the long delay in my reply. I was cleaning up e-mail today
after returning from Oshkosh and discovered I had never mailed this!
> We currently run around 180 Celsius (don't have translation chart
> under my hand)
= 356F
> and reach nearly 200/205 only during hottest weather like last summer
> when having 40celsius air
> temperature on ground!!
= 392 - 401F

Considerably warmer than my readings, which are suspect. I will have
to check the gauge and thermocouple.
> And I have a question, what are your Oil temperature and pressure
> during
> cruise along seasons!??
I run 25W60 oil and typically I see 50 - 55 psi in cruise at 2100 rpm,
depending on temperature. Oil temperature varies from 140 - 150F (60C)
at cooler ambient temperatures to top of the green arc (175F / 80C)
climbing at 30C outside temperature. Ive had to step climb when very
hot outside (37C) as the oil temperature was about to reach redline.

Good flying!

:Dan Michael
:NC81323
:Chicago, USA'