just for every body out there this is the 100% way of doing it and it also services your system at the same time.
1. close the valve tank end
2. undo pipe
3. take bottom filter housing off and clean
4. turn valve on to purge all remaining silt out then off
5. remove oil inlet pipe from burner unit put in a bottle of water and using bike pump, pump from tank end until oil runs clear( this will clear out any silt)
6. replace oil inlet pipe to burner unit
7. undo bleed nut and pump bike pump until oil flows freely, then tighten up.
8. remove bike pump attach pipe at tank end again.
9. open tank valve pull oil height valve as this will allow air trapped tank end to escape.
10. crack off bleed nut, start burner when it starts to rumble after 10 secs tighten nut and hey presto it will fire
matt the oil running out vetran