I have to agree with the OP here. He bought a brand new engine that appeared to be defective, and he has every right to badmouth OFNA for not replacing it. Lets say you bought a brand new Ipod from a reputable electronics store dealing on ebay, and the Ipod was defective and would not even turn on let alone play music. Lets also say that no one would replace your ipod, and when you talked about it on the ipod forum half the posters told you "you deserved it" for buying it on ebay or "shut up and stop bitching, shit happens". I can tell you right now I would not be feelin too hot.
I realize we're not talking about Ipods, but this guy deserves his money back. He was sold a bad product, that's not his fault and it shouldn't come out of his pocket.