SC. 120 4 stroke G5 glow plug petrol conversion

This engine was converted to electronic ignition using an ignition unit from hobbyking and a magnet ring/sensor bracket from Morris Mini Motors and it ran beautifully...........This engine run was a first test using an O.S G5 glow plug, the magnet ring and sensor bracket are still fitted to the engine but have been disconnected. With a small amount of tuning we got the engine to idle reliably at 2500 rpm and peak at 8050 rpm with a smooth transition using an evolution 16 x 6 prop.
The engine sounds pretty loud in the video but the exhaust was aiming directly at the camera and in reality didn't sound much different from when it ran on glow fuel.......the major advantage was that it literally sips fuel as the main needle was only open 1/2 turn and it ran so clean that there was no exhaust residue whatsoever...........so far so good.

[@ronitsingh85]

i did not know such a miracle gas plug existed!!! now i will try with my engines as is first with the G5 plug. cheap fuel and longer run times, hell yeah!

[@MGChen-hh7wf]

Good job ! Did you run petrol on it ? I thought that the attached ignition unit might have used for running petrol rather than glow fuel, while the OS G5 was for petrol mostly. If so, let me know the percentage of the oil that you mixed. Thank you

[@chrislarkins]

Yes it was running on petrol using the G5 plug, it was a 35:1 mix using fully synthetic 2-stroke oil.

[@MGChen-hh7wf]

Good, thank you for your prompt reply. So the mixed oil ratio was about 3%. It's very nice to know you did such good test without using CDI ignition. I'll do the same test on my OS FS40, but I might apply 10% of 2T oil first. I already did the same test on 2-stroke ENYA 30SS using octane 95 with 15% 2T-oil. But a friend on this site said that 8% is good enough, higher ratio oil will bring thick carbon stuck at the top of cylinder inside. I read somewhere from our local forums that the bushes of the piston rod might get broken owing to insufficient oil mixed. They said normal petrol engines have ball bearings on their piston rod, so using 3 - 4 % oil is good enough. While they suggested using 8% oil for glow engines that have bushes on piston rod only for avoiding the issue.

[@tritonmovies3222]

the saito fg and evolution engines run 20:1 so you should get away with that mix

[@gabrielhuang2343]

did you real fly it ? how it work ? it very easy to overheat ?

[@RBAERO]

Are you using the same compression ratio as using in glow?

[@chrislarkins]

Yes exactly the same, there were no mechanical mods to the engine

[@27andyD]

ive just done the same conversion from morris,but i like the look of the g5,have you changed the compression or is it a standard engine.

[@chrislarkins]

The engine is completely stock with no head shims or any other mods. The main needle adjustment is very sensitive so my next experiment is to machine the needle to give a finer taper, I have read elsewhere that this helps to make it less sensitive.