I installed new fuel tank access plates with feed tubes and fuel return fittings in both tanks of the Monk. This allows me to plug the old fuel feed fittings located at the bottom of the tanks which is not good if those fittings leak or fail and fill the bilge with fuel.

Now I can select which tank to fed the engine and also select which tank for the return fuel to go back into, thereby having excellent control of fuel distribution between the two 30 gallon tanks. The Monk’s new Yanmar is burning less than a half gallon an hour at about 2400 rpm that gives me 9 kts, about 65% power. This with only 60 hours on the new engine. I’m very pleased with this engine and now I have at least 120 hours of fuel range.

 

Flange routing

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Using a carbide tip router, I made a flange along the edges of the access plates. Routing aluminum works well - but you have to keep moving or the cutter will gum up with molten aluminum and use a carbide tip, a plain steel tip will quickly gum up from heat.