When were the Engine Back Preassure issues solved on C400

[hornloaded1]

I am in the market for a C400. I have been reading about the back pressure problem on the Westerbeke 42B in the C400.
Can anyone tell me when Catalina corrected this problem on new boats? Someone told me 1999 when the MKII came out. I find it hart to believe that Catalina continued to manufacture a defective system for so many years. If it is true, than I can't consider pre-99 boats because the only way to know if it was damaged is to do a compression check or disassemble the motor.
Any insight into this issue is appreciated.

Thanks
Doug
Oxnard, CA

[Cruisingdad]

certinaly anything in the MKII is ok. If you get a westerbeke, many were changed to a 3" exhaust. You can check that. Not all the engines had issues. Still, a compressin test is not a bad investment on an old diesel. The remedy, should you not have a problem on the boat you are considering, is to pull a 3" exhaust. Please understand that I was not tech editor during that so all of my information is second hand. However, I can tell you that none of the Yanmars have that issue.

Brian