I recently purchased a Waterman 52 BCHR that was restored before purchase. It writes very well, no flow problems/railroading but it does something weird.
I can write a couple of pages and then it acts like it's running out of ink in mid sentence. The first time, I figured it had run out (surprisingly in a short time) but when I pulled the fill lever over the sink, it sprayed quite a bit of ink. I figured it was an aberration.
Fast forward, I flushed it with water and filled it again with a different ink.
I've again written a few pages and it started drying out in mid sentence. I remembered the first time and I gently lifted the lever a couple of mm and it sprayed ink. Now it's writing again...
It's not like it's a hard start caused by a nib drying out it's in mid sentence and it fades, then railroads, and stops writing all together.
What causes this? I know it's an old pen but it's pretty simple design. Could the sack be twisted? Is there a way to fix it?