REFLECTOR:Oil Congealing -- Is our Nose Cooler "Sandwich Pick-off" Protected?

[Bob Jackson]

Thanks for the thoughts and info about oil congealing.  I think in most
cases Scott is right -- it's a non-issue.  Especially if your situation is
"normal" in terms of engine/airplane set-up and operating scenario.  For
example, in normal weather, altitude, and flight duration conditions the
on-engine cooler's Vernitherm (at least my IO-550N has one) should bypass
oil around that cooler until the engine is up to normal operating
temperature, and once the Vernitherm is open the hot oil flow through the
cooler should prevent oil congealing under normal conditions.

But, as Richard's story points out, there may be unusually cold weather
conditions combined with unusually long, high altitude flight legs (and
maybe this was an engine without the pressure bypass valves on the oil pump
screens and cooler that Scott's article describes?) where the oil can still
congeal in the main oil cooler, even while flying!

Another issue is whether or not the standard "sandwich oil router" that fits
under the oil filter and we use on the Velocity to send and receive engine
oil to/from the nose cooler includes it's own high pressure bypass valve.
If not, and if the nose cooler lines or the cooler itself contains congealed
oil, it might be very difficult or impossible to establish normal engine oil
flow and cooling due to a congealed oil "obstruction".

Does anyone know if the "sandwich oil router" that we use for the nose oil
cooler lines contains it's own Vernitherm and/or pressure relief bypass
valve?

Bob Jackson
Velocity XL-RG
N2XF