Removed primer / filter body, gave it all a good clean out with high pressure brake cleaner and air line. Not much visible muck. No change will not even try and start now. Primer is going stiff after about 4 pumps. As it was dry for once, decided to remove the main pump. Did notice that when I removed the fine filter it was only about 90% full, would have expected the primer to have filled this up. I have removed the gear lift pump from the back of the main pump. Cannot see anything obviously wrong with it. It rotates ok, the drive from the main pump is fine. Gear pumps are generally pretty trouble free, a talking nearly £200 for a new lift pump, so not keen on this unless I know it is at fault. I can buy a second hand pump complete for around £200. Could there be a problem anywhere else? Pipe connections all appear fine when I removed them, the fuel cooler plate behind ECU visually looks fine, no obvious sign of leakage, I have removed it to get pump off. Also checked the fine filter housing, again can’t see anything obvious, blown out with air line. Could be a case of stumping up £200 for second hand high pressure and lift pump complete, refitting and hope!