My SIIA 2.25 petrol occasionally stalls from what I believe to be fuel starvation. I have replaced the fuel pump, carburetor, fuel filter and now I will put in a new fuel line from the fuel pump to the carburetor. However, I noticed that the clear fuel filter is not filling very fast at all. Just a trickle. I have had fuel starvation issues for months. What should I do next? Is there a way to measure the correct fuel flow?