Kobota M108S tractor workshop manual

Hi all I’m looking for the timing procedure for a kubota M108S tractor, I’ve been called to a job where the fuel pump and cog have been removed and the engine was not timed to TDC before removing it and when I have tried to line it all up the tractor will barely run. I’m not sure if I’m getting it wrong or something else is amiss Cheers in advance