That happened to me. My friend had a '65 Formula S and needed the engine done. I pulled and sent the long block out b/c I had no time to do it myself. Got it back from a local rebuilder, dropped it in and started to hear a faint rod knock after about a month. Yanked it back out and dropped it off and that same shop to check out.
One of the rod bearings was smoked.....all scored up. All the others were beautiful. Those clowns tried to say it was from a lack of oil......just one rod bearing. :wack: I would have to choose a HIGHLY reputable shop to do any of my rebuild jobs now. It was bad enough that I had to pull the sucker back out on my time, just to be blamed. I figure maybe they didn't clean the crank or block good enough before assy.
When I brought the engine back in to their shop, I was just WAITING for them to try and pin it on me too.....LOL......friggin' people sometimes.....