I am pondering a possible acquisition of a Pilot Custom 823 and I only have one concern. I have recently become more sensitive to being able to maintain my pens over the length of time I own them. Specifically, I want to be able to address common issues that are likely to emerge for a pen over its operational lifetime. With the Custom 823 and other pens with filling mechanisms that use a seal (viz. piston-fillers), it is likely that the seal will lose its lubrication and cause the operation of the mechanism to become stiff. It happened before with my Lamy 2000 but I was able to unscrew the section and access the interior of the barrel, enabling me to apply a dab of silicon grease to restore full smoothness to the piston seal.
As far as I know, pilot does not advise unscrewing the section with the barrel to reach the rod's seal without removing the whole housing from the rear of the pen. I know it is possible to do this, but I am uncertain of the risk that it entails. Based on your experience with the Custom 823 (if any), how difficult is it to lubricate the seal if it causes the mechanism's operation to become stiff? Do I risk serious damage or causing performance issues with the pen if I unscrew the section with the barrel (viz. cracking the resin) to perform this maintenance task?
Thank you for reading, I look forward to your responses.