Usage:
D339, D342, D353, D379, D398, D399 Engines
The 5P6595, 5P8607 and 5P8664 Liner Seat Inserts are used for repairs of cracked cylinder counterbores in the above engines. Correct installation of these inserts is necessary during repairs of the counterbores. If the inserts are not correctly installed, there will be more cracks and combustion gas leakage. The result is failure.
For correct installation, Face A on the insert must be in contact with Face C in the counterbore. See the Illustration. But, THE LOWER FACE B OF THE INSERT MUST NOT MAKE CONTACT WITH FACE D IN THE COUNTERBORE.
If face B of the insert makes contact with lower Face D in the counterbore, the load on the face will cause cracks. The cracks will permit the insert to move down in the counterbore until Face A makes contact with Face C. The result is combustion gas leakage and, in short time, failure.
To make sure there is clearance between the lower face of the insert and the counterbore, measure from A to B on the insert. Then, measure from C to D in the counterbore.
THE INSERT DIMENSION MUST BE SMALLER THAN THE COUNTERBORE DIMENSION. IF THE INSERT DIMENSION IS LARGER, THE COUNTERBORE (FACE D) MUST BE MADE DEEPER.
Before installation of the insert, put a thin layer of 3S6252 Sealant on Face D in the counterbore. This will fill the clearance.
Other articles on the liner seat inserts are in ENGINE NEWS with the dates that follow:
September 28, 1977
July 13, 1977
September 13, 1976
Special Instructions, Form Numbers SMHS7049 and SMHS7221 also have information on use of the inserts.
Wrong and correct insert installations.