:welcome: Howard 79 to iboats. Always great to have a new member join us....
I looked at '91, '92 and '93 Evinrude 200 HP engines and I didn't see any vents that could be installed but one way. I didn't see any 200 xp models listed at all. So if you can post a picture or three, we can offer better opinions and advice, If you care to look at the '92 Evinrude engines, type in boats dot net and supply the correct info and take a look. JMHO.