Fuel Polishing Systems - Need Help!

[s/v Jedi]

Originally Posted by Cheechako

If you have an old boat and are going offshore by all means polish your fuel. Once that's done do you really need an onboard system? Seems you ought to be using your fuel faster than that. Maybe consider not filling one tank after it's polished and empty. Only fill it before you make a real long trip like Panama to the Marquesas. Just a thought.

Cheech,

You're thinking from a nice marina slip in the USA. If you wander around like we do you are much better off by not counting on those services available at all. You must be self sufficient or end up being the "whiner of the anchorage".

Also, in the US you can just go to a fuel dock and get fuel. Here, you better start with talking to others who just got fuel to learn how bad is was (it's always bad...) and keep an eye on it so you notice when they get new fuel so you can go a couple days after that. When you get fuel, you want to get all you can carry.

A polishing system is cheap. It's the extra filter and one or two pumps and some brass fittings and valves. But there's many bad ways of doing it which can introduce more trouble than it's worth and I saw some of that in this thread already. My schematic is the right way and sure the bleed/boost pump can be omitted if you don't require that. But you must have that extra pick-up from the tank sump (instead of T-ing into the engine supply line) and you must have that extra filter.

About the GPM rate of the Walbro pump: if you need higher volume, you also need a bigger filter, like the Racor 900. Check the max flow of the filter you intend to use!

cheers,
Nick.