LATCH AS 2253187 - Caterpillar

3516B (1NW) Generator Set EnginesDescription of Change: A new turbocharger exhaust coupling is used in the turbocharger groups on this engine. The new coupling is required because the counterbore depth in the turbocharger turbine housing (where the turbocharger exhaust coupling fits) has been changed from 22.22 mm (.875 in) to 15.88 mm (.625 in).Adaptable To: The new 165-4190 Coupling has replaced the former 127-4421 Coupling in the 145-7990 and 145-7991 Turbocharger Groups. The new coupling is effective with 3516B (1NW116-Up) Generator Set Engines. The illustration shows the locations of the new couplings (1). The 145-7091 Turbocharger Group (part of the 145-7990 Turbocharger Group) includes the 116-6262 Turbine Housing. The 145-7092 Turbocharger Group (part of the 145-7991 Turbocharger Group) includes the 116-6261 Turbine Housing. If the counterbore depth (for the exhaust coupling) is 15.88 mm (.625 in), the new 165-4190 Coupling is required. If the counterbore depth (for the exhaust coupling) is 22.22 mm (.875 in), the former 127-4421 Coupling is required.
145-7990 or 145-7991 Turbocharger Group.165-4190 Coupling (1).Rear face of engine block (A).Turbocharger Turbine Housing (B).Exhaust Elbow (C).