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PAI Industries · Engine
321285
In stock · ships from Knoxville
This is an external fuel injector seal kit for Caterpillar heavy-duty diesel engines.
Confirm the part fits before you buy. Applications and interchange numbers are researched and audited per part.
Verified fitment for 10 applications
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All confirmed applications for this part number.
Caterpillar
Peterbilt
Western Star
Caterpillar
Peterbilt
Western Star
Verify engine serial number and injector type before ordering. For ACERT engines, confirm seal compatibility. This is an external seal kit only; it does not include internal injector components.
Part data verified against 5 catalog sources
Numbers this part supersedes or interchanges with. Showing 11 of 11.
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It contains the O-rings and crush seal needed to reseal a single injector where it fits into the cylinder head, preventing fuel and oil leaks. Technicians replace these seals whenever an injector is removed or if there's evidence of weeping, as failed seals can lead to fuel dilution in the oil, coolant contamination, or performance loss. One kit services one injector; a full engine set on a six-cylinder model like the 3406E or C15 requires six kits.
Part Number: 321285
O-RING INJECTOR SEAL KIT/ OEM 2481394
Dealer: Post Onsite
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