I think the Chinese Briggs factory started up in the 1990s, but there will be others on this site who are better informed on it than I am. It was at about the same time as the engines were redesigned and acquired a different series of model numbers, with a letter in the first block instead of all numbers. The Chinese ones seem to be all black.
Production of the large engines and the I/C engines continued to be in the US, but I don't know if they are still made there now, or whether that will continue. The only production I know went to China was the el cheapo aluminium bore small mower engines such as your new one. As you have already noticed, it need not mean they are bad engines. By the way, Honda make their small ones in China too.
