EC300 dies slowly at idle when warm

[Jakobi]

Originally Posted by Nocams

Oem carbs have been both 38 and 36mm. do you have a screw top (as 1)or a cast slim top retained by 2 small screws(as 2)??? if you have the later,there will be a hex shape in the top with either 36 or 38 cast in.
once this is established,many here can give you their recommendation.

This. Topic has been covered many times. A little searching will help.

Any pictures of the fit? Your carb shouldn't be contacting the frame anywhere. My 13 can touch the cap against the frame if it's rotated over too far, but generally has significant clearance.