I have a 2006 4 stroke 15 hp outboard that began to misfire badly and cut out at higher rpms. Took it home and found out it had 1 and 1/2 qts too much oil in it (Still can't figure out why). Drained the oil and it looks good. The compression is 140 in one and 150 in the other. What could I have possibly done to it? Any help would be appreciated (you can make fun of me if you want.... I deserve it)!!!