John,John Danicic wrote:So next step is a system to keep it clean. I would like to install a separate pick up for the fuel polishing system which will extend into the sump so that the fuel polishing system could be working while the engine is running.
Any one have any experience doing that? Let me know.
Sail on
John Danicic
CD36 - Mariah- #124
Lake Superior- The Apostle Islands
CDSOA #655
You've described essentially the same process we performed about four years ago on Ariel. It was also at that point that I installed a new filtration system and fuel polishing circuit. We have had some crud since then, but we haven't lost our engine because of it.
Our system does not allow polishing while the engine is running, which certainly has its advantages, but it doesn't require a dedicated supply and return either, making the system a little easier to install. The reality, of course, is that any filter is polishing the fuel when the engine is running. The thing I really like about our setup is that I can use the fuel polishing pump to prime the system in a matter of seconds after filter changes, and I don't have to worry about introducing air into the system. I'll often switch over to the polishing circuit while the boat is dockside - especially after a lively sail - and leave it on for a couple of hours. The Walbro pump has the capacity to turn over a tank of fuel in less than an hour. Our season on Lake Michigan is short enough that this setup takes care of all our polishing/motoring needs without requiring more than a seasonal filter change.
If you're looking for a polisher setup that will work with the engine running, why not follow Mainesail's example? Looks ideal to me.
You may have seen it before, but here's our filtration/polishing system.
Two Racor 500 FG's - 10 microns to 2 microns.
Old R24s - lower right - is now part of a secondary filtration circuit to allow changing 500 FG filters while underway. The switch at left controls the Walbro fuel pump for polishing.
Schematic of filtration system.