Caterpillar original Caterpillar 387-9431 fuel injector replacement for OEM C9 diesel engine spare part new injector original new injector

Engineered as a precision-metered high-pressure diesel injector, the 387-9431 common rail fuel injector delivers dependable atomization and stable fuel delivery for heavy-duty C7 and C9 diesel engine platforms. This replacement injector supports engine repair, generator maintenance, marine engine service, construction machinery overhaul, and fleet rebuild programs where consistent injector performance is critical to combustion efficiency, emissions control, and long-term reliability.

Multiple OE and cross-reference numbers — including 387-9431, CA3879431, 10R-9003, 20R-8069, 328-2580, 293-4074, 267-9710, 573-4231, and 20R-8846 — enable buyers to identify the correct injector across different supplier catalogs and search systems. Public parts data links this injector to C9 generator set, C9 marine engine, C9 industrial engine, C9 petroleum engine, and SR4B generator applications, while aftermarket listings commonly reference 330D, 330D L, 336D, 324D, 325D, and 329D excavators. Correct fitment must be verified by engine serial number, old injector number, and engine arrangement number before purchase to ensure full compatibility.

For optimal service life, operate with clean diesel fuel, replace fuel filters on schedule, drain the water separator, and keep the fuel tank free of water and sediment. Diagnose hard starting, rough idle, black or white smoke, misfire, low power, or high fuel consumption by checking injector return flow, cylinder balance, injector coding, spray pattern, and diagnostic trouble codes. Store injectors in sealed packaging and use professional testing and calibration equipment when required.