I've spent a long time looking at how I can run an LR diesel engines on alternative fuels.
From what I've read, Lucas fuel pumps seem to be unfriendly to vegetable oil,
bio is less of a problem.
Bosch fuel pumps appear to take it all in their stride.
Ther are acres of web sites- try a Googling Vegetable oil car engines.
Remember that if you are discovered using non tax paid cooking oil in your car, the UK customs and excise people can not only fine you, they can immediately confiscate your car - for ever.
gdb