My thoughts suggested experiments:

1. Have you tweaked carb adjustments leaner/richer from light seat (how many turns)?
2. Was any of the fuel line bad enough debris could be in the tank and was the fuel filter replaced or checked?
3. Is the new line in the tank too short or long (out of fuel or restricted??
4. Have you tried the old carb to see if it will still run in the side position (to say carb issue)?
5. Have you peeped in the new carb for debris at the int fine filter?

What have you found by this point? Please share your experimenting and results. Good Luck!

I fixed it! All I did was rotate the fuel line by 180 degrees in the tank so that the little arrow is now pointing out instead of in. During my test the trimmer did not die.

I have another trimmer, an FS-180, that I'm fixing for a friend. Its problem is that it will not idle. It starts fine and runs at high throttle but dies at idle. I rebuilt the card and that didn't make any difference. I find that if I set the choke to about 75% on, it will idle, but then to run I have to hit the throttle at the same time that I turn the choke off. Any ideas? What could be wrong with the carb?

Thanks,
Tom

Sounds like itâÂÂs sucking air at the carbâÂÂs base or crankcase. Carb cleaner or etc might sniff out the leak by spraying joints, might chang the rpm while idling.

I got the FS180 fixed by putting blue silicone (RTV) between the carb and the intake manifold. This must have solved and air leak and now it idles fine!

Tom