12/20/2000 10:05:33 AM
Greetings. I hope everyone has a very Merry Christmas. Mine was almost
ruined this past Saturday. I departed the airport in Tampa, bound for Ft
Myers to deliver some Christmas presents. Shortly after departing the
pattern I noticed the smell of burnt oil. I proceeded cautiously but then
noticed that the cockpit was becoming filled with a hazy smoke which
prompted me to immediately return to the airport. Fortunately my oil
pressure stayed in the green as did my EGT and CHT temperatures.
Upon shutting down, I saw a stream of oil running out of the bottom
cowling. After removing the bottom cowling and dropping the water and oil
radiators, I discovered that the oil return line which runs from the banjo
fitting on the bottom of the crankcase up to the oil reservoir tank, had
"carbonized" from heat. The line had turned brittle as glass, was filled
with cracks, and crumbled in my hand when I removed it. The affected area
of the hose was the first 6 inches coming off the bottom banjo fitting.
This area is directly above the muffler and close to the Turbo housing.
(I'm running a 914 engine).
I did have a firesleeve over the oil line, but because of limited clearance
between the banjo fitting and the bottom of the crankcase, there wasn't
room to slide the firesleeve such that it covered the last couple of inches
of oil line.......and that's where the damage occurred.
I called my local Europa friends, Marvin Alvarez and Bill Stewart, to alert
them to inspect their hoses. Both of them discovered heat damage and
carbonization of the hoses.....perhaps just on the verge of the kind of
failure I experienced. Marvin actually had heat damage which burned up his
firesleeve and got to the oil line underneath the firesleeve. Another
Florida builder, Jim Brown, reported a similar past experience requiring
him to replace the hose at about 100 hours. Upon comparing notes among us
builders, and upon consultation with Rotax, we determined that each of us
was using a different kind of hose. Apparently Rotax supplies one kind of
hose, and Europa supplies several variations of different hoses, none of
which will withstand the heat generated in Turbo 914 engines. It seems
that this hose is critical and that supplied hoses are not suitable.
We're all trying to sort this one out and do not yet have a solution we're
100% comfortable with. A local rubber and hose supplier here in Tampa
sells a "high temperature / high pressure" hose used in many automotive
racing applications. The Florida authorized Rotax Service Center replaces
all hoses with this one. We'll probable try that and see if it holds up.
In the interim, everyone please do an immediate inspection of their oil
line to inspect for heat damage. The failure of this line can cause a
cockpit fire, which can really ruin your Christmas holiday. I think this
only applies to 914 applications, but you 912 drivers might also take a
look.
As we ultimately arrive at a final fix, I'll post again to this forum to
let you all know how it turned out. If any of you have had a similar
experience, please let us all know. This is serious stuff! It scared the
wits out of me!
Regards,
Garry Stout
N4220S A060
(813) 878-3929
FAX (813) 878-5651, Internet ID Garrys@att.com
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