Pretty amazing engine

[Gary Dowler]

And then this, form the "it had the virtue of never having been tried" file........

[Gary Dowler]

Being turned with electric motor from behind. He has another video of a two cylinder Cox that sounds like only one is running.

I don't know. The sound seems odd but the engine is behind plexiglass.

[Scott Richlen]

Do not show this to Young Daniel!!!

[Ian MacNeil]

Where's the castor trail in the exhaust?
Oh, no exhaust.

[Dan McEntee]

That plexiglass would be covered in exhaust oil.

    The prop is in front, blowing back against the engine and cylinders. So the exhaust is going the other way. I wish the video had shown it winding down and stopping. That would tell you something.
  Type at you later,
  Dan McEntee

[Mark Mc]

Sorry, 45 years of running Cox engines makes me "Bull!"  Eight cox engines, even four or three would be very loud.  I've done three.  And no matter where the prop is blowing, the cylinders, especially the lower ones, would be covered in oil after a few seconds.  I'm not buying it.  The only noise I am hearing is the gear mesh.

Mark

[Robert Zambelli]

I found this G-Mark 30 around 20 years ago at a swap meet.
It's made up of 5 G-Mark .060 engines, each with a spur gear driving a larger gear on the output shaft - ratio is around 2:1.
A single small 060 size carb feeds the engines.
The firing order is 1-2-3-4-5 and can be set differently but as built, one engine fires at a time.
It also has a supercharger.
The exhaust feeds directly into the gearbox for lubrication.
The arrow indicates the exhaust port from the gearbox.
It's incredibly smooth and quiet.