319 tip and larger you should be able to use a 60 mesh filter. if you are using a 317 tip or smaller, you should have a 100 mesh filter. If you have properly matched the filter to the tip you are using, it could be the paint. If your pump is pumping ok, you do not need to rebuild your pump. Double check your filters for size and condition (rips tears, holes etc), or replace with new.
I always called early so my paint store could shake all my cans before I got there unless they just got them in. I will strain my paint too, seems needed when using machines with the elctro-mechanico clutch drives, little pistons and flip type recirc valves will make you pull out your hair if you don’t take the time to strain paint. Also make sure there is a long hose on the machine, seen some take these off, but there needed or you can get hour-glass’n or poor paint performance. Hope this helps.
