5 cylinder radial running

gbritnell

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Gentlemen,
This is the completion of an engine that I started over a 1-1/2 years ago. I has posted the complete build log on the other forum before this one was started. For those who aren't familiar with this build or for those who followed it on the other forum I have finally made some progress with getting it running.
I had purchased a 12 inch 3 blade propeller (plastic) not knowing what the engine would do with it. In my initial running I found out that the prop didn't have nearly enough mass to allow the engine to idle or at least have some semblance of an idle so late last year I machined up a flywheel that I had with hopes that it would allow me to make adjustments especially with the carburetion. I got the flywheel fitted but it was so late in the year that I really didn't want to spend time in the cold, closed garage experimenting so it would have to wait until the weather changed in this part of the world.
Well the nice weather is here and it was time to pull the radial out and see if all the hours of redesign were worth it.
Although the engine is fully oiled with a pressure system I used a little of my left over premix gasoline from the snow blower to to make sure all the new parts were well oiled. The engine started almost instantly and after a few runs I had the needle and air bleed adjustments fairly close. Aside from the lower 2 cylinders still spitting oil the engine seems like it can be made to idle a little slower and and it revs quite nicely even with the heavy flywheel. I haven't fooled with the timing yet. It's running around 25 degrees advanced. It has a Hall trigger which is operating an S&S ignition unit. It's running on 86 octane pump gasoline.
gbritnell
http://youtu.be/EyX_GbTmitQ
 
5 Cyl should probably swing at least a 17 inch three or 4 blade well. I do a considerable bit of RC modeling and can tell you that a 4 cycle engine that turns slower at peak RPM will swing a much larger prop at lower RPMs extremely well. I would shoot for about 6500 RPM as a max and swing as large of a prop as you can until max rpms fall below your target. That will help cool the engine and also protect it from overspeeding if you unload the prop in a hard dive or other airobatic type of maneuver. Prior to my exit from RC modeling due to poor eyesight I was building a 1/3 scale CAP 232 and a 1/3 Scale Edge 540 both with big block engine requirements for good flight characteristics. The smaller of the two had a 1.2 cubic in supercharged 4 stroke and the larger was running a 1.08 CI 2 stroke with a pipe to maximize top RPM performance. Both planes would have benefitted from larger or multi cylinder engines to really take there performance to the next level.

Bob
 
A little history on the Morton M5 Radial Engine. It was never meant to power anything. It was designed as a teaching aid because there were not enough Radial Engines for this purpose. The big guys were in service in arecraft and not many were available. Many mechanics cut their teeth on the Morton. It later became the Burgess-Morton M5. These engines , the originals, are highly prized by collectors.

"Billy G"
 
George: Thats a real beauty. And it runs nicely. Congrats. Roger
 
That is a sweet project gbritnell, thanks for sharing.
Interesting to know alittle of the history on the Morton M5 Radial Engine, thanks Bill Gruby.
cheers
Bill.
 
really nice job
it sounds like it has some power
steve
 
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