80 piston numbers

Discussion in 'General Questions' started by howard, Sep 10, 2015.

  1. howard

    howard New Member

    can anyone tell me what the stamped piston numbers mean? I might need to match spares someday. Thanks, H.

  2. crassius

    crassius Well-Known Member

    many years ago, I measured several

    I've seen '2' thru '4' here and in measuring it seems that each number indicates 20 micrometers oversize (.7 thou in inches, so a #4 is 80 micrometers or 3 thou in inches oversized)

    I note that many pistons sold separate from motors have these numbers and are probably assumed to be used in cylinders that have some wear on them.
    howard likes this.