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PAI · Hardware & Fasteners
321222
In stock · ships from Knoxville
This is a hydrogenated Buna N (nitrile) O-ring with a dash size -113.
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Caterpillar
Caterpillar
Used on multiple engine configurations within the 3400 family; confirm your exact engine model and injector requirements.
Part data verified against 5 catalog sources
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It seals the fuel injector on Caterpillar 3400 series diesel engines. Injector O-rings can harden or crack over time, leading to fuel or compression leaks, so they are typically replaced whenever injectors are serviced. The material is chosen for good fuel and heat resistance.
Part Number: 321222
O-RING CAT 1171385
Vendor: PAI Industries
Dealer: Knox Trailers
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