It depends on what kind of sea boat it is. You can usually find where it is in the owner's manual. If you are not the owner of the boat, then ask the owner
keep contact between the tank and fuel spout
Place the tank on the dock or shore to fill it
keep contact between the tank and fuel spout
keep contact between the tank and fuel spout
Yes, If your pulling a vacuum in the fuel tank, the fuel pump cannot deliver fuel to the engine and will stall. Check the fuel tank vent hose and fitting, a common problem is wax build up in the fuel tank vent screen. If you replace the fitting, remember it is a requirement to have the screen in the fuel tank vent. Quick test is to run the boat until it stalls and remove the fill cap, listen for vacuum release.
Tank size on that boat should be 22 gallons. Sea Ray website has downloadable specs on older boats.
30 gal
keep contact between the tank and fuel spout
The answer depends on the size of the tank and the fuel efficiency of the boat as well as whether or not it has any other source of motive power.
Search on-line for "Diesel fuel polishing" and the name of the state you are in. There are services that specializes in cleaning these tanks and reconditioning the fuel.
Don't ask me @-@
Drive it around about 4 hours