I broke down a few weeks back?

I thought I had ran out of diesel but I never.
The greenflag mechanic said I needed a new starter or to fix the wire to it.
I have since done both and it still wont start,
Everything else works on the van except it wont start with a turn of the key.
it start with a bump start but that's a major pain in the a**.

Any help on what the problem could be would be very helpfull.

thanks