Hi Graham and Judith,GraNJud said:
as far as I can see from their web site the Bessacarr 435 is a C-class with an MTPLA of 3.4 tons and a length of over 6 metres.
For such a van I would consider both mentioned engines as underpowered, but at least the 1.9TD definitely is. I once had it in a rental van (also C-class, but only 3.0 tons MTPLA and 5.5 metres) and already there the lack of power was more than a nuisance. Setting it in motion even on level ground was only possible with heavily grinding clutch and almost floored throttle.
A van of this size and weight should have at least the 2.3JTD, if not the 2.8 in my opinion. But if there is no other choice for you, then take at least the 2.0JTD. The difference in noise level is also very much in favour of the JTD.
There are no specific issues known regarding starting a JTD. Mine (OK, it's the 2.8JTD) always starts at first try.
Best Regards,
Gerhard