AFA Industries has released a technical bulletin for technicians familiar with Detroit Diesel Series 60 engines.
AFA says Detroit has designed a new piston for use in current and older model Series 60 14-L engines. This new piston has a longer skirt and a new design Top Ring and second compression ring and ring land. AFA says the new piston (P/N: 23537126) has a skirt length of 65.3 mm compared to the old piston (P/N: 23533282) skirt of 57.3 mm. See highlight #2 in the illustration below.
“The new piston is heavier than the old piston and cannot be mixed in an engine,” AFA says. “You must use either all new design pistons or all older design pistons in the engine to insure no vibration or failures. You must also use the correct piston ring set designed for the specific piston.”
The Top Ring also has been redesigned with a new material for better durability, the company says.
The second compression ring has been changed from a keystone design to a rectangular design. A new ring set part number has been created to service the new piston design (D23537529).
AFA says the old piston design has not been superseded to the new piston. The older style will remain a serviceable part. The pistons are not inter mixable in the same engine application due to weight differences. If the pistons were intermixed an engine vibration may result. AFA says factory remanufactured engines will come equipped with the new pistons installed.
