DaveLeonard wrote:

Although I now have about 55 hours on N4VY, I have not yet done the
maneuver
most likely to cause significant engine problems... planning a trip
in the
plane.  That is until Tuesday when right before the trip I sprung
significant oil and coolant leaks (separate)

I did some form flying on Tuesday a.m. trying to keep up with some
other
RV's.  A buddy of mine was in his RV-8 with a 180+ h.p. with a c/s
prop.  He
was lead and would set 19" MAP at 2500 AGL and I had to run about 27"
MAP to
keep up with him.  (although my plane is not jet fully faired, I
thing the
turbo back pressure is hurting a little.)  We chased each other
around the
sky at speeds a little higher than I had been allowing previously.
At a
couple of miles out from the field the coolant pressure low warning
came on.
When I landed I was disappointed to coolant briskly dripping from the
cowl.

The culprit turned out to be a crack in an alum tube at a flare
fitting.
The line had about a 2.5 foot run before it's other end without
support.
Bad design.   I am very glad it was coolant and not fuel, that it
happened
at my home field and not at some far away airport on my trip.  I
fixed both
the tubing and design issue in a couple hours, almost ready to go on
my
trip, when I noticed the oil leak.

The leak, pretty brisk, is coming from the oil cooler itself near one
of its
mounting points.  I combination of vibration and dynamic pressure
probably
caused a split of the cooler near its mount, though I still can't see
exactly where it is coming from.  The oil cooler is a Setrab.  They
come
highly recommended as being tough.  Again, it was probably a design
issue
for placing too much stress on the mounting points.

I haven't yet come up with a good plan to solve the issue.  In the
mean time
I had to rent a C172 to go on the trip... and that really hurt.  :-)

Dave Leonard

We have had nothing but trouble with non Mazda oil coolers.

Paul Lamar

I have not seen Dave's installation so I don't know what precautions he
took, but the Setrab instructions state that the cooler  should be
isolated from all  vibration.  Mine is rated to 600 psi. If Setrab's
claims can be believed,  I don't think  dynamic pressure blew the
cooler.  I  have not worked on mounting the oil cooler yet.  But I am
going to proceed with great care, even more so after Dave's experience.
Ed knows quite a bit about isolating radiators and oil cooler from
vibration.  Maybe we can talk him into writing about this for ACRE.
Ed.  are  you listening?       Jerry

 
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