Originally Posted by Alastair

All my BioDiesel is filtered to 1 micron, then passed through a 1 micron Absolute filter....

Due to the nature of the vehicle fuel system, you dont want particles running round the fuel-system.

The effects of particle and wear are slow and cumulative....

Your car may be fine for say, 20K miles by filtering your fuel to 20 uM but after that may start to show signs of wear...

If you filter to 1uM then that figure could well be times by ten or more....