I picked up this pen at a discount when Pear Tree was going out of business and it's endured some abuse over the years. I've taken it apart a few times to clean it including pulling the nib out of the feed to flush it with water from the sink. Increasingly, however, it's been giving me performance problems. Recently I noticed that the nib no longer goes back into the feed tightly and it is prone to some leakage. Did I screw something up, like perhaps accidentally flush an O-ring out of the feed? Is it user-serviceable if I did? (I may be in the market for a new workhorse pen soon if this is going to continue to be a pain without an easy fix. My budget would be somewhere between $20-80 and I'd want a F/XF nib which makes the Japanese pens an appealing place to look.)