What is a Cummins Injector Cup, and what does it do?
The injector cup is a critical sealing component in Cummins diesel engines (e.g., ISX, ISB, or 5.9L/6.7L models). It sits between the fuel injector and the cylinder head, creating a tight seal to:

Prevent coolant/fuel mixing.

Withstand high-pressure fuel delivery.

Protect the cylinder head from corrosion or erosion.

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