I mounted my GP460 engine in a position where the canister-type air cleaner points straight up. I'm thinking any prankster can pass by and pour a whole can of soda into the slots, thereby destroying my engine. Until I could devise a permanent solution, I simply placed an empty 7-ounce tuna can atop the air cleaner when I parked it.
Last night I figured out how to make a permanent fix. First, I marked where the 4.25"(diameter) tuna can's edge was, on the 3.875"(diameter) air cleaner-canister. Then I added another .25" Next, I unscrewed the air cleaner canister and drilled 27 holes into it with a 3/8" drill bit, above the marked line. Before I screwed the tuna can "bonnet" on, I placed a .25" spacer between the tuna can and the canister. This will allow the canister to breathe through its the original top vents as well as the new 27 holes.
Now no one can pour stuff into my aircleaner, ANNNNND the engine breathes more freely with 27 more vent holes. Sorry, no pics, but it looks pretty cool.