Got it! That also happens a lot to VW's with their Solex carbs. Stupid brass pieces pulls out. I usually pin mine with with a punch. Never thought about threading them.By the way. IMO the most important thing to check is the fuel line going into the carb. Many 850s have caught fire because the brass fitting fell out of the carb. I personally remove the fitting and install a threaded one on every 850 I work on.