How to maintain dry ink in a fountain pen and Pilot V7 pens?
Fountain pens and metal-tipped technical pens rely on capillary action and flow limiters to deliver a controlled amount of ink.  They're manufactured to precise tolerances, and there isn't really any form of adjustment.  If the pen is clean and the ink is fresh, and the ink is in the general range of viscosity the pen is designed to handle, it should work.
The combination of the pen and a third party ink should deliver an ink line, although the characteristics of the line may not match what you want or what the pen manufacturer's ink produces.  For example, a lower viscosity ink may result in more ink being delivered, so the line will be wider and contain more liquid; it may take longer to dry, resulting in more spread and a less-well-defined edge unless the ink is much faster drying.  A higher viscosity ink may result in a thinner line.  In extreme cases, the pen may have trouble keeping up if you move the pen too quickly.
The pen will have prescribed maintenance, which is basically cleaning.  There isn't any different maintenance for third party inks, it may just require doing it more often.  If the third party ink is faster drying or higher viscosity, it will more quickly thicken inside the pen and dry in the nib or tip.
So if you want to use a &quot;dry&quot; ink in a pen designed for a &quot;wet&quot; ink, you will have the least problems if you use the pen regularly.  That will keep ink moving through the nib or tip to keep it free of dried ink.  It will also result in using up the ink inside the pen before it thickens.  If you want to use that pen-ink combination only occasionally, you would be better off emptying the pen and cleaning it before putting it away (unused ink can be returned to the original bottle).