If you are reconditioning your Freelander engine there are three grinding levels for a crankshaft:
0.25mm or 10 thousandths (0.01) of an inch
0.50mm or 20 thousandths (0.02) of an inch
0.75mm or 30 thousandths (0.03) of an inch
If you fit a bearing which is smaller than the amount the crankshaft has been ground by, oil will leak through between the bearing and the crankshaft and hence oil pressure will not build up and the engine will not run.
Often it is not possible, however, to get bearings as undersized as 0.75mm, this is generally an indicator the bearing manufacturers do not believe the engine will run effectively if this size of bearing is used.