Oil temperature questions

A few weeks ago while flying through -17 degree C air aloft, I spotted what
appeared to be really a low oil temperature indication of the
turbo-normalized, IO-520 engine in my V35. For a few moments, the oil
temperature was around 125 degrees F.

When I landed I contacted my mechanic, who verbalized that he suspected the
oil thermostat (the valve that controls the oil flow into the oil cooler)
was bad. In his experience, he stated that the oil temperature should be
around 180 degrees F.

After removing and inspecting this thermostat, he concluded that the valve
was not seating properly and that most likely allowed oil into the cooler,
despite the lower oil temperature. Thus, I authorized the replacement of
it (it was under warranty).

These days and with a new thermostat installed, I am only seeing oil
temperatures of no higher than 155-160 degrees F while flying through air
of +1 to +5 degrees C. Does this still seem low?

BTW, I did share this observation with my mechanic and he called Tornado
Alley (manufacturers of the turbo-normalized system). TA was not alarmed
with the 155 degree F oil temperature.

For some additional information, the oil cooler is located on the top of
the firewall, directly behind the engine, rather than in the front.

--
Peter

I have a much smaller engine in my C-172. This is a conversion with a
Lyc O-360-A1A. I calibrated the temperature probe and marked the
temperature when the indicator needle first came into the lower green
(135F) then the point of 180F (the magic oil temperature). I can never
get the engine to read 180F. It runs about 145F to 160F. This engine
does have an oil cooler on it.

Ross
KSWI

Peter R. wrote:

A few weeks ago while flying through -17 degree C air aloft, I spotted what
appeared to be really a low oil temperature indication of the
turbo-normalized, IO-520 engine in my V35. For a few moments, the oil
temperature was around 125 degrees F.

When I landed I contacted my mechanic, who verbalized that he suspected the
oil thermostat (the valve that controls the oil flow into the oil cooler)
was bad. In his experience, he stated that the oil temperature should be
around 180 degrees F.

After removing and inspecting this thermostat, he concluded that the valve
was not seating properly and that most likely allowed oil into the cooler,
despite the lower oil temperature. Thus, I authorized the replacement of
it (it was under warranty).

These days and with a new thermostat installed, I am only seeing oil
temperatures of no higher than 155-160 degrees F while flying through air
of +1 to +5 degrees C. Does this still seem low?

BTW, I did share this observation with my mechanic and he called Tornado
Alley (manufacturers of the turbo-normalized system). TA was not alarmed
with the 155 degree F oil temperature.

For some additional information, the oil cooler is located on the top of
the firewall, directly behind the engine, rather than in the front.

That's easy. Once you make sure that your oil temp probe is accurate,
just block part of the airflow over the oil cooler with duct tape.
Experiment the amount of the coverage you need to get it to 180F.

I do this all the time in winter.


nrp wrote:

Another symptom of persistently low oil temperature is an engine with
little blowby - a good thing, although 180 degF still remains the
operational goal. My 172M is cold blooded & I wish there was a way to
get it to warm up more consistently.

A buddy of mine has an RV-6 with an O-360 in it, and he built a hinged
aluminum cover plate over the oil cooler and connected a standard
push-pull control cable, like a carb heat cable, to the cover so he can
fine-tune the airflow thru the oil cooler in flight. Too bad we can't
just simply do that to our certified airplanes or it'd make the wings
fall off or something like that.

Ross Richardson wrote:
I built a plate that mounts to the oil cooler, much like the Piper Arrow
kit. It helps, but the opening is too large. Next winter I am going to
experiment with a smaller opening. I believe the Piper winterization kit
hole was 1.5" dia hole. My opening is larger that that. 100F yesterday
in North Central TX, Guess I ought to take it off.

Don't know about your engine, but on my Lycoming O-360-A4A the vernatherm is
an oil cooler bypass valve and when the oil is hot it closes to force all of
the oil through the oil cooler. If it doesn't seat properly, oil leaks past
the oil cooler and the oil gets too hot, not too cold.

--
Best Regards,
Mike
http://photoshow.comcast.net/mikenoel
"Peter R." wrote in message
...
A few weeks ago while flying through -17 degree C air aloft, I spotted what
appeared to be really a low oil temperature indication of the
turbo-normalized, IO-520 engine in my V35. For a few moments, the oil
temperature was around 125 degrees F.

When I landed I contacted my mechanic, who verbalized that he suspected
the
oil thermostat (the valve that controls the oil flow into the oil cooler)
was bad. In his experience, he stated that the oil temperature should be
around 180 degrees F.

After removing and inspecting this thermostat, he concluded that the valve
was not seating properly and that most likely allowed oil into the cooler,
despite the lower oil temperature. Thus, I authorized the replacement of
it (it was under warranty).

These days and with a new thermostat installed, I am only seeing oil
temperatures of no higher than 155-160 degrees F while flying through air
of +1 to +5 degrees C. Does this still seem low?

BTW, I did share this observation with my mechanic and he called Tornado
Alley (manufacturers of the turbo-normalized system). TA was not alarmed
with the 155 degree F oil temperature.

For some additional information, the oil cooler is located on the top of
the firewall, directly behind the engine, rather than in the front.

--
Peter

A buddy of mine has an RV-6 with an O-360 in it, and he built a hinged
aluminum cover plate over the oil cooler and connected a standard
push-pull control cable, like a carb heat cable, to the cover so he can
fine-tune the airflow thru the oil cooler in flight. Too bad we can't
just simply do that to our certified airplanes or it'd make the wings
fall off or something like that.

That is just too bloody intelligent. I can't believe that's not a
standard feature on every Spam can...

Stupid, stupid, stupid FAA rules....
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

In article .com,
"Jay Honeck" wrote:

A buddy of mine has an RV-6 with an O-360 in it, and he built a hinged
aluminum cover plate over the oil cooler and connected a standard
push-pull control cable, like a carb heat cable, to the cover so he can
fine-tune the airflow thru the oil cooler in flight. Too bad we can't
just simply do that to our certified airplanes or it'd make the wings
fall off or something like that.

That is just too bloody intelligent. I can't believe that's not a
standard feature on every Spam can...

Oil temp doesn't seem to be much of an issue with the cherokee 140.
So such a control would be appear to be unnecessary for at least
some aircraft.

--
Bob Noel
Looking for a sig the
lawyers will hate

Jay Honeck wrote:
: A buddy of mine has an RV-6 with an O-360 in it, and he built a hinged
: aluminum cover plate over the oil cooler and connected a standard
: push-pull control cable, like a carb heat cable, to the cover so he can
: fine-tune the airflow thru the oil cooler in flight. Too bad we can't
: just simply do that to our certified airplanes or it'd make the wings
: fall off or something like that.

: That is just too bloody intelligent. I can't believe that's not a
: standard feature on every Spam can...

There is an STC for the Cherokee 180 with the firewall mounted oil cooler
to add just such a device. At least in my airplane the oil temperature
stayed at 180 without such a device, thus I never pursued it further.
--
Aaron C.

Bob Noel wrote:
In article .com,
"Jay Honeck" wrote:

A buddy of mine has an RV-6 with an O-360 in it, and he built a hinged
aluminum cover plate over the oil cooler and connected a standard
push-pull control cable, like a carb heat cable, to the cover so he can
fine-tune the airflow thru the oil cooler in flight. Too bad we can't
just simply do that to our certified airplanes or it'd make the wings
fall off or something like that.

That is just too bloody intelligent. I can't believe that's not a
standard feature on every Spam can...

Oil temp doesn't seem to be much of an issue with the cherokee 140.
So such a control would be appear to be unnecessary for at least
some aircraft.

Cherokees, especially the 140, are notorious for needing the airflow
thru the oil cooler restricted to almost zilch in colder weather, else
they'll never get the oil up to the 180 degrees necessary to boil off
the water that gets into the oil from combustion blow-by gasses.

Hi Aaron,
You don't happen to know who has the STC or what the number is do you? I
searched the FAA site and came up empty handed.

"Aaron Coolidge" wrote in message
...
Jay Honeck wrote:
: A buddy of mine has an RV-6 with an O-360 in it, and he built a hinged
: aluminum cover plate over the oil cooler and connected a standard
: push-pull control cable, like a carb heat cable, to the cover so he can
: fine-tune the airflow thru the oil cooler in flight. Too bad we can't
: just simply do that to our certified airplanes or it'd make the wings
: fall off or something like that.

: That is just too bloody intelligent. I can't believe that's not a
: standard feature on every Spam can...

There is an STC for the Cherokee 180 with the firewall mounted oil cooler
to add just such a device. At least in my airplane the oil temperature
stayed at 180 without such a device, thus I never pursued it further.
--
Aaron C.