Pe :
Have you tried POREX filters ? (not sinterized) .
See specs here :
http://www.porex.com/by_product/by_p...fm#javascript;
When i discovered this kind of clunk-filters, and after many hours testing , i said : i will NEVER use felt filters. Hundreds of porex filters sold and distributed, and ALL customers agree with me. I have some stock of felt clunks, but i never offer them to modellers. I offer porex filters instead (same price).
Also i've found replacement filter screens at very very low price, this filter can be dismantled. The filtering screen is fixed with a G ring. and can be easy changed.
Advantages :
Same price, can be changed the filtering screen for a fraction of the clunk, constant fuel supply, no bubbles, and NO felt particles on carb screen, more heavy than felt type , special O'ring to avoid bumping inside the tank, .........
Regards