leaking lower unit fill plug

97 yam proV lower unit fill plug keeps leaking, have tried new washer, tighten very tight and still leaks.
any suggestions? thx

Teflon tape on threads

Make sure you don't have two washers on there. It's easy enough to overlook the old one, or part of it still being in place. Been there done that.

Found it, cracked washer. Took back to repair shop fixed in no time