It could be one (or more) of a number of things and blocked fuel filter would definitely give these symptoms, so if it hasn't been recently changed, a good idea to get a new one on there. Best to try a process of elimination, by changing one item, trying it out, then move onto the next, if that didn't solve it.
I'm curious as to why it wouldn't rev from idle though - I don't suppose you were operatng the chokes, rather than the throttles?
Are all the connections ok on your new fuel line?
Alternatively, you may have a dodgy electrical connection, which is cutting out from time to time - these can be difficult to fix, as they seldom occur when you're looking for them.