Mercury - High-Volume Water-Separating Fuel Filter Remote Mount Systems 35-8M0079963. Overview. This filter is the typical spin-on canister you'll find on remote-mounted fuel systems, and it's one of those "don't skip it" maintenance items. Its job is pretty simple-keep water and fine debris out of the fuel before it reaches anything important. What makes this one stand out is the extra filtering material inside, so it can handle heavier fuel demand without choking things up. Swapping it out tak