01/10/2001 08:37:37 AM
Since I was the one who started this thread, I thought I'd share my
summarized thoughts with everyone. I believe that the ultimate solution
would be to remove the sump banjo fitting, cut off the tip of the fitting,
and weld on a male threaded fitting. Utilizing this threaded fitting I
would then fabricate a steel oil return line and route it up to the oil
reservoir. Once getting past the heat sources (turbo unit and exhaust
manifolds) I would mate a conventional flexible hose to the steel hose for
the last 3 or 4 inches before the line connects to the oil reservoir. This
is necessary to absorb engine vibrations. With this setup, it's impossible
to "burn" the oil line.
Now, that's not what I did. After much research and lots of advice from
fellow Europa flyers, I determined that a flexible hose made by
AeroQuip........model #666, would suffice. This hose is made of teflon and
is covered with a stainless steel mesh. It is supposedly rated to 350
degrees (F). I further wrapped the hose with a 1/4 inch thick flexible
firewall insulating material which I believe is asbestos filler with a
silver foil material on each side. My friend Marvin Alvarez says he put
his welding torch to this material..........about 2,000 degrees (F), and it
didn't burn.
I've only put a couple of hours on the plane since making this mod, but so
far, so good. Another Europa pilot in California has used the AeroQuip
hose alone, with no further insulation, and has successfully flown 200
hours with no problems.
How this whole problem started is as follows. Rotax supplies a fine, high
quality oil return hose to be used for this application. Due to the unique
oil line routing (to the reservoir) recommended by Europa, a 120 degree
bend in the hose is required just as the hose exits the sump banjo fitting.
Europa supplies a substitute hose which is pre-molded with the 120 degree
bend molded in......and instructs that their hose be used rather than the
Rotax (straight) hose. Unfortunately, the Europa supplied hose is totally
unsuitable for that application. It has no heat resistance and isn't even
internally reinforced. It's a plain rubber hose more suitable for a douche
bag than for a critical aircraft engine component in a high temperature
environment. I suggest all Europa builders/flyers replace this hose
immediately. Shame on Europa for not issuing a warning / mandatory mod on
this........years ago.
Regards,
Garry Stout
N4220S
(813) 878-3929
FAX (813) 878-5651, Internet ID Garrys@att.com
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