hi guys,i don't know alot about my outboard but i have a 77 evinrude 6hp 2 stroke it ran great the first 3-4 times i went out then i hit some rocks and rattled it pretty good after that when i accelerate it it boggs down both in forward and reverse and stalls out i checked the housing and prop,the prop is scraped a little but the bottom looks good what could it be?thanks for all the help