I have a 82 300SD with 232k on it. It runs without burning oil and runs strong. It does have a knock in the front cylinder. The mechanic says it could be one of two things. One is the pre-chamber. the other the wrist pin. Either way he told me the car could run for years with this knock and don't worry about it. I understand the wrist pins can get loose and go for a long time, but how can the pre-chamber cause a knock? To me it sounds mechanical. Any opinions?
82 300SD 232k
81 300D dead at 207k