Aresti engine mounted upside down help.
 

I bought a Hanger 9 Aresti which mounts the engine upside down. The recommend engine is a 40-.58 2-stroke or 40-.72 4-stroke.

Does a 2 or 4 stroke run / start better than the other when mounted unside down? Any other tips when mounting an engine upside down?

Thanks Very Much!

Sitney

Link to the plane.
http://www.chiefaircraft.com/cgi-bin...9Aresti40.html

RE: Aresti engine mounted upside down help.
 

sitney....

....I have an Arresti with a .60 2-cycle in it. I wanted to show you
the carb spraybar height, as compared to the tank height. This is
important. As you can see, the needle valve (which is in the center
of the spraybar) is just slightly lower than center of the tank. This
is just fine.

An inverted two stroke doesn't flood very easily, because the fuel
will drip out on the ground, rather than into the engine. The four
cycle will be about the same, because the carb is mounted behind
the engine at aprox. the engine centerline, which is close to the tank
centerline as well.

The choice is yours....flip a coin. Be sure to brace the tail feathers on
the Arresti, or they will fail if the plane is pushed. I diminished the size
of the elevator as well, it is way too large, and prone to flutter.

Check out some of the Arresti threads hear at RCU. ;)

FBD. :D

RE: Aresti engine mounted upside down help.
 

Sitney ... the trick in getting engines to run well upside down is some patience in tuning. My Aresti was running on a Saito 72, one of my pals was with an OS50SX and then an ST G51. We do not have any real starting and idling problems. One thing I found out is that the first time you start the engine for the day is always a problem, being inverted the fuel will not feed properly. Use an electric starter or flip her upside down to start her. After the first flight she will always fire up.

As for tuning I found that you need to run the engine leaner than when its upright. Means if upright you open the needle for 2.5 turns then when inverted its about 2 turns.

Priming should be only one turn or so ... do not do more if not you will flood the engine. Using a refueling valve helps when you fill up, it will ensure hardly any fuel goes into the carb as you fill up.

Take some time to tune the engine and it will run well! Mine did as I invested in some time. All my 2C or 4C engines run well inverted.

RE: Aresti engine mounted upside down help.
 

Hi FBD.
Thanks for the good info. It looks like you really lopped off some of your elevator. It also looks like you either made the CA hinges longer or replaced with something else. Any comment on that – are ca’s good enough?

Since you have had good success with the .60 2-cycle you installed, what brand is it?

I’ll do some searches on Aresti.

Thanks again.

Sitney