Upon removing my outdrive to grease ujoints, splines, etc, I found two rubber flaps with metal encased in the middle of them down in the exhaust portion of the drive - they were pretty crunchy and looked like they had been there awhile. Are they in fact exhaust shutters? If so, how do you go about replacing them, what function do they serve - how important are they?? I have the service manuals downloaded for this boat - is the replacement procedure outlined in one of them? Thanks in advance for any help!
