I sympathize with your problem but agree with Jason that it is not a filter size problem. I have a Gulf 32 with a 70 gallon diesel tank and use a Racor 15S 2 micron. It is rated for something like 15 gallons an hour when my 4 cylinder Universal 5432 uses less than 1 gallon an hour at full throttle. I just happened to change my primary filter and after 150 hours it was nearly like brand new. I change mine once a year just to be extra careful. Your smaller motor uses even less fuel and so filter size is definitely not your issue.
Long story short, your problem lies elsewhere. What I love about diesels is that they are so darn easy to diagnose, especially when compared with the modern gas engine.
I also have a Walbro pump as my electric pump, and it lies between the filter and the engine. Although my Racor has a primer pump on it to fill the system at filter changes, I have used the electric pump to do my own fuel polishing, which you may want to do as well.
Anyway, just my two cents that I wouldn't think your problem is at all related to the size of your Racor. Good luck, and keep us posted.