It's the oval style, so I popped off the wire bracket holding it down and opened it up...this is what I found:
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I feel lucky that none of the screws or washers fell down into the carb. Oil is everywhere. The foam filter element is absolutely saturated...did my best rinsing it out, but still getting big globs of oil dripping out when I squeeze it.
So...what would have caused this? I have the original air cleaner box...might it be worth it to go back to that? Also have what I guess is a "lunchbox" style cleaner. But if there's oil getting in somewhere, any of the others would have the same issue, huh?
Edited to add...I have noticed a faint white mist gently wafting out of the carb/cleaner when I've had the hood up. Not sure if that's related?