Gen II is a Mercruiser and wont fit...easy way to id is to count splines of prop shaft or easier the the prop size. If its a 10 or 11 by XX pitch its a 44 cube.
Replace the fuel lines and bulb the clean the carbs. Bet the fuel line liner has degraded and restricting fuel supply and blocking high speed jets. Looks like a aftermarket grey line...
The green finish is a anti-rust sealer coating, when installing ,it will seal the OD of seal to ID of bearing housing but it has to be installed with a straight push, no cocking or walking in.
If it has no leaks internal or external, and is a aftermarket line or bulb most likely the primer bulb. I only use OEM bulbs as the aftermarket ones the check valve/s fail.
On a 3 cylinder motor #3 will be a tad darker due it being supplied a lil extra fuel from recirc system to bottom bearing. Same way on a V-4 as #4 and #6 on a V-6.
