Re: Merc fuel coupler o-ring install Home › Forum › Ask A Member › Merc fuel coupler o-ring install › Re: Merc fuel coupler o-ring install opposedtwinUS Member - 2 YearsReplies: 968Topics: 259 October 27, 2018 at 1:33 pm #85042 Mercury pressure fitting? Sure you have the correct size orings? Should be pretty straight forward. Attachments: