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I'm trying to rebuild this carb for a backpack blower. The service manual says to remove the plastic plug on top of the barrel to access the inner idle needle to adjust it. There is no plastic plug on this barrel. It looks like a brass plug and it doesn't want to pop out. Is this a non-adjustable carb?

Thanks,
Roland

Some of the newer carbs are factory preset, with a fixed jet system and are not adjustable

Ok, that must be it. Thanks for the info.