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PAI · Engine
321318
In stock · ships from Knoxville
This PAI 321318 kit contains the o-rings needed to seal the fuel injector sleeves on Caterpillar 3406E, C15, C16, and C18 diesel engines.
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Verified fitment for 4 applications
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Caterpillar
Caterpillar
Part data verified against 4 catalog sources
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The injector sleeve sits inside the cylinder head and separates the fuel and coolant passages from the combustion chamber; a failed o-ring can allow fuel and coolant to mix, leading to engine damage. The kit is commonly replaced during injector service or cylinder head overhaul to maintain a leak-free seal. It includes three different o-ring sizes that match the original Caterpillar components.
Part Number: 321318
INJECTOR SLEEVE O-RING KIT CAT
Dealer: Post Onsite
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