Can anyone tell me why on my Holley 650 vacc. secondary. carb. on my 307" 72' Malibu has bur marks. One place is badly melted. This plastic gasket is on the carb neck where it meets the air filter. When I touch it, it seems to have some powder burns. Also under my air cleaner cover there seems to be some carbon stains/film.

You must have experienced backfiring and/or carb fires. Have you had these problems at any time ? Perhaps just in the past. If you still are, explain the symptoms and ask for help.Flames outside the engine are not good.

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