OPERATOR AR 3511957 - Caterpillar

Family Of EnginesNew thinner spacer plates are available for parts service. A list of the new, thinner spacer plates follows: For 3406 Engines ... 6I3189For 3408 Engines ... 6I0860For 3412 Engines ... 6I0861
These new spacer plates are 0.076 mm (.0030 in) thinner than the standard spacer plates. The new spacer plates provide an alternative to counterboring all the cylinder liner seats in order to increase average liner projection to within the specification range. The cylinder liner projection specification range is 0.03 to 0.15 mm (.001 to .006 in).
The new thinner spacer plates should NOT be installed to achieve liner projections greater than 0.15 mm (.006 in).Measure cylinder liner projection. See the appropriate Service Manual Module. The new thinner spacer plates CAN NOT be used unless: * Inspection of cylinder block indicates no measurable erosion greater than 0.03 mm (.001 in) deep directly under cylinder liner flanges.* Cylinder liner projection does not vary by more than 0.05 mm (.002 in) between cylinders.* Cylinder liner projection does not vary by more than 0.05 mm (.002 in) between the measurements for any one cylinder.
This type of damage must be corrected by counterboring the cylinder liner seats and installing the appropriate stainless steel inserts prior to final assembly of an engine with new thinner spacer plates.