Dear All,

(posting is about my 1983 380SEC).
In the Mercedes manual for my engine (116.963) it says that the piston marking (e.g., 1,1+,or 2) should correspond with the respective marking on the engine block. ("The group number is also stamped into the crankcase mating surface. The piston group number (e.g., 2) must correspond with the group number of the cylinder bores (series manufacture)").

Now here is the problem: All my pistons are stamped 1+; about half of my cylinders are stamped 2 and the other half 1+ (in a seemingly random order). I doubt that this engine was ever disassambled before. Could you guys who have (not) seen anything like this before comment? Is this serious - if yes, how is it possible?

Thanks!

__________________
1983 560SL Megasquirted (originally 380SL)

My former Mercedes:
1985 300SD ~190k
1990 560SEL
2000 C220 CDI
1983 380SEC 102k dual-chain conversion
2000 C280 70k (sold)
1987 300DT (W124 - sold)
1972 220D (sold)
1971 220D (sold)