one of my pilots which is standard except crm 250 carb sounds like its takeing in air, when i rev it up the revs start to drop but then holds on to its revs, sounds like it is stuck at about quarter throttle but the slide is all the way down. so i turn off the key and it makes no difference the same happens when i try the kill switch on the steering wheel it just keeps on revving. as you can imagine the first time this happened i was running around like a headless chicken, an engine that runs with no spark :shock: even my hand over the air intake made no differance!. by this time i am in a right flap, luckily i had an idear to turn it on its roof, that worked
looking at the plug it is running very lean and i have tryed spraying petrol around carb rubber, bottom of the cylinder etc to try to find an air leak but nothing. my other pilot also has a crm carb but that one runs ok.
If i run the engine on tickover and turn off the key or use the kill switch the engine stops as normal. has anyone else come across this problem or suggest a possible cure, i dont fancy this happening whilst i am driveing it putting it on its roof to stop it is a bit drastic.