Quick update for you. Fixed it!
It was that pesky gauze mesh filter at the inlet hose banjo.
Clogged with brown crud.....
Washed in acetone, air dried.
Works perfectly now!!
There are other posts on this pesky filter on here, so follow those for location and instructions.
Will post piccys when I have time.
'90 TD42 Safari 12V MT CRGY60 - Cyprus import
'93 TD42T Safari 24V AT WRGY60 with beer cooler - Jap import