I have a new to me 2004 Glastron 175 SX with the Volvo Penta 3.0GLM-C motor. It has a manual fuel pump on the side and has an integrated fuel filter built into the pump. The operators manual says that it is a 10 micron water separating fuel filter (pn: 3855104). Is that true? Is it really a water separating fuel filter? Is the screw on the bottom a drain or for disassembly? Thanks for any info on the subject.