Obviously here on this forum we don't say biodiesel is a no-no.
Please ask his friends why they say that and get back to us with the reasons.
Also what is meant by "his engine is ruined".
Details please. There are many ways an engine can be 'ruined' and very few are 'potentially due to the biodiesel'.
We would love to hear detail of how an engine can be ruined due to biodiesel.
Very much more common IMO would be engine ruined by poor quality or contaminated commercially available distillate.
IMO well made 'home-brewed' biodiesel is a superior fuel. Far superior to anything commercially available.
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