Paul,
here are some photos of a local 5151 Mustang with a Suzuki/Geo engine.
The thing I noticed was that the engine mount didn't have any
triangulation. There is one piece of tubing connecting the right and
left sides of this mount, but I'm not real sure that the design is a
good one. The builder says that the engine is sufficient as a
cross-brace, but it is mounted with lord type mounts, and will allow a
bit of lateral movement. Would it be possible  for you or someone with
more experience than me to do a structural analysis of this mount? I can
provide more detailed photos if you'd like.

http://picasaweb.google.com/john.marzulli/EAA1440ProjectVisitLoehle5151

Brian Trubee

It is not just the lack of cross bracing.
Right up there with the worst motor mount designs I ever saw :)
You will need an FEA but I don't have that capability.

Paul Lamar ...No rotor no motor.

Hey Brian,


Getting close to flying your bird? I may be up your way in my plane in April
if I can get the annual done promptly. I would like to stop in and see some
of other guys as well.

His motor mount is not greatest but I think it can be fixed.  You are
correct, it does need some type of cross brace.  The motor can't perform
that task  unless it is bolted securely to the frame sans rubber mounts.
Strangely it looks like it IS bolted directly at the rear starboard side and
left to float on the front. That mean the mass of the engine and prop forces
are going to flex the motor mount.  Crack!!


 I think Paul will comment on bigger issues though. The cooling system for
one is an accident waiting to happen. Band clamps, hose, and water pipe
plumbing, etc. looks like it was purchased at the local hardware store.

He would save a lot of money and perhaps his life if he redid the systems
now.


Cheers


Doug

Yeah, if that "black pipe" is painted galvanized water pipe, it will
fatigue crack where it is threaded into the engine. If it is screwed
into aluminum, it will make a nice battery there and fail in time from
corrosion alone. If it is really "black pipe" ( i.e. - natural gas pipe/
malleable iron ) it will not crack so easily but will corrode much faster.

Also, is that a pre-heater in the cooling line ? If so, it probably had
instructions with it to mount in vertically as it works like an old
percolator coffee pot.

-dave


The Rotary Engine NewsLetter. Powered by Linux.
ACRE NL web site. http://www.rotaryeng.net
Copyright 1998-2007 All world wide rights reserved.