so then, decoking the engine is going to be hard to avoid if I am to run this type of lister exclusively on SVO (my only readily available carbon neutral fuel here in blighty) because elsbett technicians reckon that any distributor-injection-pump made by CAV, Lucas, Stanadyne, RotoDiesel or Delphi is unsuited (too delicate) to pump SVO. However I've just read this scientific study conducted in Europe somewhere, which concluded that if you make a bioblend mix, the fuel will behave like diesel at 80 C. Moreover, according to the findings, it will burn a lot cleaner, producing a lot less soot. I've found a 340watt fuel heater now all I have to do is get the thing loaded up to the hilt....
keep on truckin
tommy
p.s. thanks for all your advice.