I am having a frusating time with this engine!

The engine is brand new and fitted into a TWM 50cc Sky Link

The engine starts and runs really well, that is until the aircraft gets in the air. After about 2 to 3 min the power drops off and I have to land. It is like the throttle is being brought back to idle. The engine does not stop running and has to be killed after landing.

I have checked and set up the high and low mixtures, I have doubled the air opening in the cowl to fully expose the cylinder and the ignition battery is fully charged. I have even changed the throttle servo incase it had a fault.

I have read some good and bad points about the FTL, but dont want togive up on it yet.

Oh yes, It has been run in.

Any ideas greatfully received

Warwick Laken

Is your fuel tank vented? Max

The tank is vented and all pipes in good condition.

Hi Warwick,

One possible cause is the plug loading through too rich a blend (still on running in mix of oil to petrol?) or a fault in the ignition module that manifests after a little running/heat/load. Does the motor exhibit the same symptoms with a prolonged run on the ground? Other possible faults are with the diaphram in the carby (unlikely on a new motor), or improperly seating reed valve (if it has one).

Good Luck,

Colin

Hi Colin,

Thank you for ypur tips, * will check them this evening. Fuel is 32:1. Engine appears fine on the ground.

Cheers

I have a Brison 2.4 that was doing that and I fought it for a couple of weeks. It turned out I was just off on the tune but the way the carb is mounted the needles are facing the prop without much finger room and I was trying to tune it by shutting it down and twisting the needles. I just couldn't get it right that way. I mounted fuel line over the needles and risked body parts but with it running I just adjusted the high end then the low and got it corrected. It was a risk, nothing I would ever tell anyone else to do but I did it and it worked for me.[&:]