Veggie oil in a marine diesel engine ?

[MogM]

I am new to boating and as yet still haven't found the boat of my dreams (and pocket) but reading a car magazine article about using vegetable oil to fuel a car I wondered if it would work in a marine diesel.

Has anyone tried it ?

 

[Elessar]

haven't tried it but looked into fitting conversion systems to boats a while back.

As I remember it (which may not be full and complete):

Basically you're either going to refine the oil into biodiesel or burn it direct by adding a system of heaters to the fuel system to lower its viscosity. With the latter you have to stop and start on "dino diesel" which makes it pointless for stop/start cars but boats tend to stay on for longer spells so it starts to look promising.

But......

The bio stuff will get all the **** out of your fuel system and will block filters like mad for a while, thereafter will just block them often. You can engineer your way round this by engineering a system like lifeboats have with parallel filters so you can isolate and change one with the engine running.

Then there's the issue of acquiring 1000's of litres of chip fat. You can buy it on ebay - check out the prices, it's far from free. Plus a way of getting said fat to the boat.

But the killer for the project is that if you run the engine for long spells at the same RPM it encourages a build up of the hard shiny fat you get on your chip pan. This glazes over the bores and kills the compression on the engine. Not any issue in cars but it makes it useless for boats.

I remember concluding positively that it's not worth the effort.