Motor is a 95 Mercury EFI 175. Problem happens right after start up. It studders/clunks for a few seconds after I put it in gear. It idles fine in neutral. Sounds kinda like a clunking sound or the prop is hitting something? But when it reaches 2k and above rpm it smooths out? It just started doing this recently. It does it on every start up and after it's put in gear both foward and reverse. I have recently changed the plugs and they looked ok, a little black and some oil. Thanks in advance!