My Zenoah G-20 was flying fine today when I thought I heard it pop them I lost throttle response. The engine will start and idle for about a minute then quit. It will not rev up when it is running though the throttle is openning and the engine sounds like it is starving for fuel. It is getting fuel but not enough for acceleration. It has maybe two gallons of fuel through it and I removed the side plate and made sure the screen was clean. Has anyone had a similar problem?

Harry

I had a similar problem with an SPE 26 starving for fuel. It turned out that the gasket between the carb and insulator block had shifted, blocking the pulse hole that runs the carb fuel pump. Its something you could check.

Thanks, that was the first thing I checked. The gasket is lined up. This engine has been running great, I have it in a Dymond Modelsports Rearwin Speedster and another one in a Great Planes P-6 Hawk. The engines always starts easy and run great, this is the first problem I've had with one and I'm hoping someone can give me some insight into what is going on.

Harry

Is your battery real real good? The Zenoah EI will use up a 2000 mah battery real fast.

I'm thinking that may be a problem, I switched batteries the other day and stuck in an 1100, I have a 3800 I will put in and give that a try. Is it possible not enough amperage will cause a timing problem or not a hot enough spark?

Harry

Okay, a friend called and clued me in to the fact that Zenoah uses a soft woodruff key on their shafts. A sheared woodruff would account for the loss of power after the pop. I can't get the collar off now and will need to use a puller. If I remember correctly the collar came off pretty easily before so I think the woodruff key has sheared and got the timing off. That and the actuator for the EI is hitting the module right at TDC. I think it should hit BTDC, I'll know more tomorrow after I get the collar off the prop shaft. I'll need a wheel puller to get it off though.

Harry

...sounds like you are on the right track, keep us posted on your findings.

Sure hope you get it all sorted out soon enough and as Chad said, do keep us informed on your progress.

Karol

When you stick things back togather check the air gap between the sensor and magnet.