Zenoah G-23 Help

Looks about right to me...

Not so sure about this, but should you be using a different oil or mix for running in? The Zenoah's do need a good few hours before they reach full power...

Not surprising when you put so little oil in the mix...

My experience is that it's happiest on a 16x10, 17x8 or 18x6, still, there's no harm in trying...

-- Philip Rawson

While not exactly familiar with that particular power plant, I have some knowledge of the oils in use. Most of the IMAC guys will run an engine on

Based on the 18-10 specified for that engine, de-rating the prop to

Cheers, Fred McClellan The House Of Balsa Dust

I wouldn't break in the engine on Amsoil 100:1, but after it is broken in, that is a good oil to use. Even my Amsoil dealer, who is a very active R/C pilot, told me not to use Amsoil 100:1 while breaking in an engine. I sure like the Zenoah G23's. After not running mine since October, yesterday I went out and it started on the second flip.

Greg

First run (test stand) on my G-23 with regular gas and Lawn Boy ashless oil @ 32:1 and a Zinger 18-8 prop netted an average of just over 6,800rpm. Subsequent runs (after almost a gallon of fuel flown thru it and a slight tweeking of carb adjustments, showed an increase to an average of 7,100 rpm. These results were with the factory canister style supplied muffler. I haven't yet tried a Bennett style exhaust on this engine. After getting more time on your engine, you will also notice a gain in rpms. As for prop choice -- testing will show the results. I stayed with the 18" prop for ground clearance on my plane.

Happy Landings! Rich

Thanks for all the help.

Oh, btw, it has a Bennett's in-cowl muffler.

I ran one 14-oz. tank with Amsoil. I'll switch to natural oil to finish the break-in, then go back to Amsoil for flying.

I want to try the 20-6 prop, since I want pull instead of speed on the Dr1.

Dr.1 Driver "There's a Hun in the sun!"

I'm amazed you are swinging an 18x8 that fast. My G23 prefers a 16x8. If you get too much prop on it, the rpm's will go way down and you won't have any accelleration for takeoff. Be careful. I think a 20x6 is overkill on that engine.

It has been stated by those that imported the G-23 that a 15x8 is the ideal prop size for sport flying. The engine is ported to spin up near 10k rpm.

I would be concerned about overheating with the very large prop sizes mentioned.

Ed Cregger

I agree Ed. 18x8 is entirely too big for the g23. Gonna cook it!

Heck yea. An 18-8 is a prop you'd more likely want to put on a G-38 or Q-42, not 23cc of anything. I find that a 16-8 is the perfect prop for my two G-23's.

MJC

I ran a 22-6 on a G-38, and it was great. I appreciate all the small-prop suggestions, but I'm not building a giant scale pylon racer, people, just a Fokker Dr.1. I want pull, not speed. That translates into more diameter, less pitch. Dr.1 Driver "There's a Hun in the sun!"

I know what you're up to, Gerald. But I would keep an eye on the spark plug.

Ed Cregger

Aha! Might burn it up? Or load it up? Do I need to change plugs right off the bat? Dr.1 Driver "There's a Hun in the sun!"

You may find the stock plug is too hot.

At the risk of preaching to the choir, taking a plug reading is fairly simple.

With a _new_ plug of the correct OEM spec, set the gap, torque it into the head, make sure the mix is right, and fly the pattern for ten minutes or so to color the plug. Then bring the engine to full chat for at 30 seconds or so, and cut the throttle all the way to dead-stick. Don't let the engine idle; plug 'heat' readings are only relevant when the engine is cut while in the upper RPM ranges, not when cut from idle.

Pull the plug, and look at the bottom of the center ceramic. It should be a light tan or mocha color. Most folks need a magnifying glass to see the color band.

The color of the center ceramic _tip_ is of no interest unless you've got some sort of deposit thing going on - shouldn't be an issue on a new plug.

Older plugs which have been in service a while are only useful for noting deposits, not heat range.

A good explanation of what to look at and what to see is at :