Cat bought 50% of Perkins in the late 1980's and acquired 100% ownership of them in 1997. Their disastrous foray into Chinese Perkins manufacturing has been put behind them, and settled (through the Chinese courts, surprisingly).
The corporate crooks involved in the Tianjin Joint Venture were jailed. However, the damage the Tianjin crooks did to Perkins is unquantifiable.
No-one really knows how many dodgy Chinese Cat Perkins parts were produced by Tianjin - or how many Chinese Cat Perkins engines were produced with poor assembly or build quality.
With this kind of problem, it can still be appearing 10 or 15 yrs down the track, as the low hour engines crash due to the Chinese faults in manufacture or assembly that aren't discovered until many years later.
However, Cat should still be standing behind their product, and if you have a premature failure and make a lot of noise in the dealership managers office, they usually admit to any known problem/s.
The standard initial reply is, "you're the only one having this problem". This has been the Cat standard reply since I bought my first new Cat D6C in 1966 - and the D333 had heads coming off valves within 4000hrs.
Of course, after the standard Cat reply, I found out that other local Cat owners were having the same problem! It was only when a head fell off a valve less than a week after the dealer did an engine rebuild (and they were up for another rebuild under warranty), that the dealer grudgingly admitted, "Yes, we had a batch of faulty valves - so we'll give you a full new set for free".
Now, the stupidity of the whole deal was - if the dealer had admitted the problem, first up, they would have saved themselves the cost of a full engine rebuild. :duh
Back to the Chinese Cat Perkins saga. As of December 2007, Cat built an entire new engine factory in China, and went into Joint Venture with IHI-Shibaura, the Japanese engine & tractor company, to run the Chinese Perkins engine production facility.
Shibaura has a long record of building Perkins engines under licence, and there are no Chinese involved in the QC or the management of the new JV.
The assembly-line workers are Chinese, of course - but they are working under tight Cat/Shibaura control, and QC is equivalent to any other top Cat or Shibaura manufacturing facility. This factory came on stream in late 2008.
http://china.cat.com/cda/layout?m=315919&x=7&id=1629444
http://www.ihi-shibaura.com/english/aboutus/history.html