Yes you can sue for the money. You likely will not get back attorney fees, unless you can show fraud or unfair/deceptive trade practices, which is much harder to show than simple breach of contract action. First try writing a formal demand letter, or have your attorney do so to show you are serious. If that doesn't get you the engine or a refund, then you would need to sue. Depending on the amount at issue, you can go to Small Claims. If the vendor is from out of state, your options are severally more limited & expensive.

I would echo the above advice and only wish to add - do you have any kind of a written agreement? If so, what does it say? Where did you buy the product from? There may be some kind of provision in the agreement either mandating that any legal action is to be brought whereever the company is located. Some contract disputes may evey require litigation.

Your relationship with this entity may also dictate where you sue. Are they a big national dealer? Or just a mom-and-pop type of place? You cannot sue in small claims in North Carolina if they are located out of state. Unless they have contacts with North Carolina, you may not even be able to sue them in regular court here.

As for attorney fees - good luck. It is unlikely that you will recover them unless they are authorized by a particular statute, like the claim for unfair/deceptive trade practices mentioned by Attorney Brumback.

Your best bet is to have an attorney send them a letter as noted.