Usage:
3400 Family Of Engines Equipped With Spacer Plates
Reference: Truck Engine News, November 1988, Page 1, "New Liner Seat Inserts Available".
Reference: Special Instruction, Form SMHS8222, "Installation Of 2W3815 Or 5N0093 Inserts".
New seat inserts are available to salvage engine blocks that have damage from fretting, erosion, corrosion, wear steps or cracks on top of the cylinder block under the cylinder liner flange. These new inserts provide greater flexibility and ease of repair by complementing the existing stainless steel inserts. See the chart.
The new inserts measure 0.05 mm (.002 in) thinner or thicker than the standard inserts. The nominal thickness is marked on each new insert. The new inserts provide additional repair options within each counterbore depth range. They also help alleviate the need to counterbore to the next available depth range if the original counterbore measures out of specifications.
Additionally, new thicker inserts are available for cleanup of deeper cracks in the liner seat [down to 5.26 mm (.207 in) deep]. Previously, Caterpillar recommended counterboring only to a depth of 2.71 mm (.106 in).
To ensure correct liner projection after counterboring, it is recommended that inserts be measured, to determine actual thickness, prior to machining.
Shims made from cast iron or any other material are not recommended for use on 3400 Family of Engines to adjust liner projection. Use only the approved inserts listed in the chart.
When machining is complete, deburr the edges of the counterbore with emery paper or No. 400 wet-dry sandpaper. Install the inserts in the counterbore with chamfered edge of the insert facing down and without sealant (dry).
Inserts previously installed in an engine can be used again in subsequent repairs if the inserts are measured at four locations for the correct thickness.
