A while back I called Diawa and told them of the problems I was having with the Lexa. They sent me kits that included new brass gears and washers. The only change I can see is that the spool gear is much better cut than the original. The kit also came with new lube and instructions to clean all the old lube out and replace it.
Both reels are now back to what they were when I bought them and functioning correctly. There was no charge for the kits or shipping.
If you have the original Lexa 300 and have a problem, just call Diawa and they'll send you the kits. It only takes about an hour to do the repairs.