Hello everyone im new to boating and attained and old tri-hull c-gull by sport-craft model # 1871 serial # 16008 it has an 85HP mercury 850 motor on it thats all the info i have at this time i cant find a hull ID anywhere just a plate with the above info. second where the heck is the gas cap lol i don't see one any where here are the pics i have if anyone has any input let me know like my profile name says i am new to this please be patient with me with my dumb questions. if any one has any links for tech.. info let me know id be more then great full.
Stand behind the boat, look to the right of the motor (that's the starboard side) just under the rubrail and see if the hull id number is stamped there in the boat hull itself, if not get in the boat and look under the splash well where the motor is mounted and see if the hull id number is stamped there on the inside of the transom just above the drain area.
As far as the gas cap probably not one, most likely came with an external 6 gallon gas tank and fuel hose that hooked directly to the motor with a quick connect fitting.