16hp Briggs on a Billy Goat debris loader. Had the dealer replace the impellor. One of the blades cracked at the end of last year. Got it back, started it up and I think I heard it spit oil from the marked area in the second picture. Oil is under the muffler, as shown in the third picture. It doesn't smoke a lot at an idle, but it really smokes when I rev it up. Then starts to bog down. Any help is appreciated.