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1663739
An injector sleeve for Caterpillar heavy-duty diesel engines.
It is a cylindrical metal sleeve with an O-ring that seals the fuel injector in the cylinder head, isolating it from coolant passages. The sleeve is replaced when it leaks, cracks, or corrodes, preventing coolant from contaminating fuel or oil, which can cause serious engine damage. This part is typically serviced during injector replacement or when coolant is found in the fuel system on C13, 3406E, C15, and other Caterpillar engines.
Fitment list includes models from cross-referenced part 263-4920; verify exact coverage for 1663739. Commonly used in Cat C13, 3406E, and C15 applications.
Part data verified against 5 catalog sources
Part Number: 1663739
CAT INJECTOR SLEEVE
Vendor: STOWERS MACHINERY
Dealer: KP Services Crossville
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