> Most of Mazda engine aircraft crashes are due to bad
> plumbing; fuel, water and exhaust.
IIRC, the only one which was actually an internal problem was one guy
who built up his engine without an oil pump, and didn't put enough oil
in his fuel mix.
Keith
I am familiar with that report. I think it was a Coot that
spun in and burned. Engine quit, guy turned back and stalled
due to aft CG. Ken Welter knew the guy well. The NTSB has it all
wrong. I don't know why the engine quit but it was not from a
lack of apex seal oil. The the engine will run for hours without
apex seal oil. I know of one guy that flew from Tennessee to upstate
New York with no oil in the fuel. As far as I know he is still
flying that engine several years later without touching it. Most
people remove the apex seal oil metering pump and mix 2 cycle
oil with the fuel.
As I recall the FAA or NTSB took the engine to Mazda dealer
that knew nothing about rotaries in aircraft and they
noticed the missing metering pump.
We wrote letters to the NTSB and they just stone walled us on
the subject.
-----------------------------------------
OK here is the report. As I recall the guy was using
a cheap Chinese oil cooler that we had problems with and warned
people about before. He was on the newsletter for awhile but I don't
know if he got the word on that oil cooler. He was the type of guy
that ignored good advice anyway. The oil cooler would split
as soon as the aircraft left the ground, the RPM built up
and the oil pressure built up. Happened twice before to
other people. That of course would pump all the engine oil
overboard in short order. Then the engine bearings would seize.
The company that supplied it no longer sells that oil cooler.
BTW That really doesn't hurt the rotary engine as
one guy did it on the ground. Engine revved to 10,000 RPM and seized
He chiseled the engine apart, replaced the bearings and flew it for
several hundred hours before he crashed it in the woods when trying
to land on an unlighted strip. Walked away from the crash.
I digress.
A piston engine would throw one or more rods. The Mazda requires a
robust oil cooler as the pressure can get to 150 psi when the oil is
cold and the RPM is high enough. Best to use the stock oil cooler
whenever possible.
--
Paul Lamar ...No rotor no motor.
If a stock oil cooler won't fit because of its size, are there other
oil coolers that are reasonable replacements? Earl's racing coolers
are advertised as pressure tested to 175 psi, and have samples randomly
tested to failure around 350 psi. Setrab's specifications are
similar.
Scott Gettings
I would go with the Setrab. IMHO the Mazda cooler were made
by Modine which is a heavy duty heat exchanger maker.
http://www.modine.com/
If you can find and off the shelf heat exchanger from Modine
that would be the way to go. Lots of good stuff on this
web site. They have some good pdf files on how to size
oil coolers.
Some people think the Earl's cooler are junk.
Connect a hyd jack pump to the cooler and test it to 300 psi.
Paul Lamar ...No rotor no motor.
OK, thanks. I couldn't find a Modine in the right size, but an
appropriate Setrab (about 200 cu inches) is available for less than
$300.
Scott Gettings
Scott also take a look at the 3rd gen and RX8 coolers.
The high power RX8 have two. Maybe that is true for
the 3rd gen as well.
By now there are far more RX8 in the US than 3rd gens
were ever imported.
Paul Lamar
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