if that pic of the online filter is the OP's. Then that filter has a bunch of rust in it, and needs cleaning along with the metal fuel lines and tank. See if you can get some speedo cable inside cable and feed it thru your metal lines like a mini roto-rooter. You can chuck it up in variable speed drill if you like. Those inline filters only catch a fraction of the debris, so there has to be some crap in the new carb. If you pop the top of the carb off and see sediment in the bottom of the float bowl, you'll probably have to take the carb apart and blow out all the passages. Be careful, IIRC, there are a couple of check balls you need to be extra careful of.
