bogeyp38

My Feedback: (12)

i HAVE A VERY LOW TIME GEMINI 1.20 TWIN...IT HAS NEVER BEEN FLOWN BECAUSE I CAN NOT GET THE ENGINE TO HAVE A RELIABLE IDLE...IT RUNS GREAT IN THE MID TO HIGH RPM RANGE BUT CONSISTENTLY DROPS THE LEFT CYLINDER...IT IS IN A SPACEWALKER THAT TOOK A LONG TIME FOR ME TO BUILD...ANY HELP WOULD BE GREATLY APPRECIATED....P.S. THE SOUND THAT THE TWIN MAKES IS GREAT...REALLY WANT TO FLY IT..THANX RON

Bax

My Feedback: (11)

Ron,

Without seeing the engine, we'd not know the correct reason. First, make sure you have two good O.S. Type F glow plugs.

If the engine's not had much running, then it's likely not broken-in, and the rings haven't seated properly. If it's had a bunch of high-speed running too early, the rings may not have seated, and they may never 'come in'.

You may be trying to idle the engine too slowly. We try to get around 2,200 RPM, and anything lower is extra good.

Check the fuel system for proper draw and tank location. The centerline of the tank should go through the center of the carbureetor or slightly lower. Too high or too low will give operating problems.

Hope these help.

bogeyp38

My Feedback: (12)

hey baxter, I appreciate the advice,,I do have the type f plugs<replaced twice...I,m using 30 per cent nitro fuel...tank level is good...if i need to ring this motor are parts available? thanx, ron

Bax

My Feedback: (11)

parts are available for the O.S. Max FT-120-II Gemini twin. If your engine is the older FT-120, then most parts for it are not availble. Piston rings, though, still are.