[Vwdiesel] OT diesel engine

[mark shepherd]

My father has a 1993 camper, with a 1929cc  FIAT turbo diesel engine. It is  very hard to find out about the correct timing. Alas FIAT dieselheads are still in kindergarden compared with the VW/Merc  chaps. 

The engine started playing up recently. 
It starts easily.
It seemed to loose power yet smokes under load.
Compression good, no coolant loss, but seems to be running hotter than usual and a louder clack-clack.
Found timing belt allignment marks out of sync:
At crank TDC (pulley mark), which I checked with the open valve bisecting two marks trick for accuracy, as no clutch housing mark :o(  

1)Cam is advanced one Cam Belt Tooth, and
2) VE  Bosch injector pump is retarded 1 CBTooth

However, cam pulley is fixed to cam with a locating lug on cam, yet when bolt undone, found there is at least 1 CBT slop. Not down to wear. We have now put a sleeve over the lug to centralize the fixing. 

Furthermore at TDC the pump is reading 60 thou. This seems very high, and as setting pump pulley marks with pump body would result in an even higher reading, that seems wrong.

Is it possible that 1.9TD FIAT engines, running  prechamber heads, and a VE pump and identical to VW 150bar Bosch injectors should be  timed so far in advance? IE 1.5mm, or even greater?

Why should a keyed cam have so much slop?

Mark