Friday, April 23, 2010

Is my engine sucking air?

Project from Eolian, in 2000.

After suffering several "unscheduled stoppages", as the Previous Owner termed them, early in our tenure aboard Eolian, Jane became paranoid (rightfully so, based on our experience) that the engine was going to fail. She frequently went down below and pulled up the floorboard over the Racor filters to check the vacuum gauge. The more critical the availability of the engine became, the more frequently she was down below pulling up the floorboard.

Rather than being a problem, this pointed out an important fact: One of our critical pieces of instrumentation was in an inaccessible location.

I procured another Racor vacuum gauge (one designed for panel mounting), and mounted it next to the engine hour meter on the panel adjacent to the companionway. I plumbed it direct to the inlet of the engine lift pump, by installing a tee.

Here it is with the engine running under way, showing that there is no impending fuel filter blockage.

Perhaps the most important thing that I have come to recognize as a result of this little project is that an annoyance is really an opportunity to improve, in disguise.


  1. Why not install a second fuel filter with a two way valve in front of the two fuel filters. This way if one dies then you merely flip the valve and keep going. The line coming out of the two fuel filters merely needs a "T".

    It sounds like what is needed is a fuel polishing. You can make your own with a fuel filter (water separator) going to a small fuel pump. The input is a rubber hose with a copper pipe (I have also seen PVC used) so you can get down to the bottom of the tank. The output is a rubber hose so you can put the fuel back into the tank.

    The problem is the fuel pickup is ~ .5" off of the bottom of the tank. This allows all of the sludge / water to accumulate on the bottom of the tank. When you run the engine in the slip - no problem. When you are in any type of seas you have big problems.

  2. Anonymous: Thanks for the suggestion! Eolian came to us with two steel canister filters plumbed as you suggest, plus a 900 gal/hr Racor downstream of the pair. As it turned out, the steel canister filters were empty - they had no filter elements in them! So now we have 2 900 gal/hr Racors, plumbed so that either (or both) can be in the line. (BTW, as a personal preference, I prefer not to use two-way valves since they have no "off" position - YMMV)


Related Posts Plugin for WordPress, Blogger...