thanks for the replies.

I guess I cant be 100% certain it's not a fake. Is there any definitive way of knowing? It was bought from a local supplier. Came in a Walbro box and has Walbro stamped on the pump.

I was worried that maybe I'd missed something like change a relay or upgrade the cabling to make sure there is enough current at the pump.

Maybe I was just plain unlucky, searching around the net does show a heap of failures in a short time. I think some of the comments even say that they seem to either fail in a short time or last forever and a day