Hi Guys iv been away from my subsim for far to long

Any way i was lucky enough to have a new 8800GT card So i went and bought SH4 i installed it and it looks great . i put on the latest patch and started the game everthing was great but im doing the Mission where i got to drop of a spy but ill be out of fuel to get home so how do i refuel? All so when i speed the game up sometimes it doesent get light untill dinner Time...is this right?. and all so the Fins want come down when i dive and when they do the stay down when i surface... sry to ask as i know this may have all been asked before. Thanks for Any Reply.