Bio-Diesel Conversion

   I’m excited by my upgrade plans this winter to convert Galatea into a nearly 100% “green” vessel for the 2008 season. She’ll be propelled by the wind or bio-diesel fuel.

  Bio-diesel is mostly vegtable oil. In fact, the Yanmar diesel engine in Galatea could run on pure vegtable oil. But that could pose potential problems in it’s actual use. That problem being pure vegtable oil is a highly viscous liquid. In order for vegtable oil to be used in a diesel engine it needs to be pre-heated to decrease it’s viscosity. Which is exactly what automobiles do for straight vegtable oil engine conversions.

  For sailboats, a pre-heater isn’t practical. The solution is using a blend of vegtable oil, methanol, and lye to create bio-diesel. These additives change the chemical composition of the vegtable oil to produce a fuel that has a low enough viscosity for use in a diesel engine. And the beauty of bio-diesel is that it can be mixed with petrol-diesel in pretty much any ratio. So, sailing up the coast of New England for a long trip wouldn’t be a problem with having to find bio-diesel.

  OK, the fuel is the easy part. The tough part is upgrading the boats fuel system to be able to use bio-diesel. You can’t just start adding bio-diesel in your fuel tank and motor away from the dock or mooring.

 Bio-diesel is a solvent. Over the long term it will corrode any older fuel lines or fuel pumps with older type gaskets. In the short term it would dissolve all the petrol-diesel gunk at the bottom of the fuel tank and quickly clog the fuel filters. And on top of it all, bio-diesel can leak past the engines piston rings more easily that petrol-diesel building up fuel in the oil pan.

  To upgrade a sailboat to use bio-diesel the fuel tank and the fuel lines should be replaced. Unless the boat is fairly new. But most of us have older boats so we need to replace everything.

  I was forced to remove my fuel tank, which is the entire reason I even started thinking about converting to bio-diesel. At the begining of last season, my fuel tank began to leak. It wasn’t bad. I was able to keep the fuel from leaking into the environment by the new oil absorbant pads that are sold at marine stores such as West Marine. Though, as soon as the boat was hauled out of the water this fall, I pulled that tank right out. Discovered a pin size hole underneath the tank where it had corroded.

  Anyways, with the fuel tank removed I can easily replace the fuel lines with modern lines. And of course, the new tank I install will be free of petrol-diesel gunk build up. The only things I need to do is keep an eye on the fuel pump that it doesn’t leak. And when or if it does leak, I’ll just replace it. I keep a spare on the boat. And the last thing I need to do is just change the oil more often. I usually change the engineoil once a year. From now on I’ll change it twice a year.

  I still need to do more research on the net this winter.  I want to make absolutely certain that I won’t be destroying a $7000 diesel engine. Because once that engine goes, I won’t be repowering it. I’ll be donating the boat to a worthy charity and that will be the end of my sailing days. So, if I do find out information contrary to what I’ve been reading so far I will abort my plans for upgrading to bio-diesel. So stay tuned.

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