Looking for fuel system upgrade ideas.

[Boulter]

Hi:

I have an Ontario 32 with a Yanmar YSE12 engine. I believe but am not absolutely sure that the engine has no built in secondary filter. I think this because the fuel hose attaches to where there is too much going on to be hiding a fuel filter. Also, the documentation I have shows the engine with an attached fuel tank - so I think the primary filter traveled with the tank. So I believe that the only filter I have is a 10 micrometer external. I’d like to migrate to something more robust.

The annual usage hours are likely to be low, ~ 100 as I don’t like paying for fuel, don’t like noise, and expect to eventually have sufficient solar panels for electricity generation. So while I want robust, I don’t need to be anal.

After exploring old threads a while, I think I want a secondary/guard filter of 10 micrometers close to the engine, then the fuel pump, then a pair of primary filters, likely 10 adjacent to the tank followed by a 2. (Or maybe a 30-10 pair would be better). Maybe this is overkill and a single primary filter of 10 micrometers is adequate, with a reasonably clean tank I should be replacing filters on elapsed time (annually) not running time (clogged).

Then there is the issue of valving to bypass/isolate the primary filters in order to run on the secondary for short durations if the primaries need attention under way. I would think that the right setup would also allow bleeding of the filter assembly without having to bleed at the engine when doing primary filter work, and that alone might justify a bit of effort here. Or maybe at 100 hours annual usage, it just isn’t worth doing anything extra.

The final issue is where to locate everything. Right now the filter and pump are mounted in the starboard lazarette on the galley bulkhead. This is somewhat out of the way of accidental damage, but is weak for access as from the cockpit it is very low, but I’d rather not have to climb into the lazarette to get things at eye level. There is all kinds of space behind the companionway stairs adjacent/above the engine, and would provide great access to the filters once the stairs are hauled away, but then the filters are in the way of serious engine access. Maybe with enough slack in the fuel hoses, I could make a primary filter sub assembly that could hang adjacent/over the engine immediately under the first stair step, but could then be pulled up and away into the cabin space for better engine access.

So in summary, I think I want tank, valve, primer bulb, valve, primary filter 10, primary filter 2 valve, longish run of hose, secondary/guard filter, (maybe) valve, short hose to engine. Then there will be a bypass line around the primaries with a normally closed valve.

As to what series of filters to use, certainly the Racor 110, 120 series of 15GPH filters are more than adequate flow wise, but with the filter elements double the cost of the more common 500 series, in the long run I might as well go with 500 series as long as there are not space issues.

I welcome any wisdom ...

Boulter