i called the dealer and explained the problem. they contacted NH and now there is a repair notice on it. the dealer was explaing that Nh has a new system that they pop a problem into a computer system and it checks worldwide for the same problem and finds the repair. if the problem hasn't been noted yet the techs look into it and come up with a solution. when they get enough complaints on the same problem they put a tech bulletin out with the fix, as they did with my problem. at any rate, i'm rambling here, they know about the problem and have the fix. i don't know if the tc18 uses the same orfice though.