I have the sudden shut off of an otherwise purring engine problem that I see others have had. Like others, it restarts fairly easily, especially with choke. I also have the orange material/gas in my fuel filter. Dry gas helped but did not stop the problem. Carb cleaner helped and so I'll clean/rebuild the carb and install a real fuel filter. Which one should I order and is it in you catalogue? I think I have the late model zenith 9 (with the copper tubing to the manifold). How can I be sure to order the correct gaskets? Also I have never cleaned the bowl of the annex to the fuel pump that the gas line feeds into! What is that and how do you remove it without spilling gas all over?