rear wheel bearings

[smithys ec250]

just decided to put new bearings in my dirtstars as there was play in the rear wheel, replaced all three and built back up but still wobbles so i put in a new centre spacer.....still wobbles, i was advised that there was also suposed to be a washer (not retaining clip) that fits behind the inner bearing on sprocket side which i was un sure off but tryed this and no luck (the place also sent a centre spacer aswell which was way to small so i think this may be for a newer model etc) anyways wheel still wobbles as i can feel the spacer move inside hub when bearings are in, anyone any ideas....worn hub maybe?? the bearings on sprocket side just pushed in by hand ,doesnt seem to be play in them but they will fall out if you lean wheel to one side, any help much appreciated