Caterpillar original 577-7633 HEUI Fuel Injector 20R8968 235-5261 387-9435 573-4231 for C9 Engine E330D E336D Excavator original new injector

The Caterpillar C9 Series HEUI Fuel Injector 577-7633 557-7633 20R-8968 20R-8064 235-5261 is an industrial-grade diesel fuel injector assembly engineered for CAT C9 diesel engines used across excavators, motor graders, wheel tractor scrapers, compactors, and various heavy-duty construction, mining, and petroleum applications. Built to support direct replacement compatibility, this injector delivers precision fuel metering and stable atomization, helping restore engine performance, throttle response, and combustion efficiency in demanding field conditions.

This fuel injector assembly is designed for broad C9 engine application coverage, with multiple cross-reference number matching including 10R-7222, 387-9438, 328-2577, 20R-9433, and 10R-4764. It fits 330D, 336D, 336D2, 340D2 excavators, 140M, 140M2, 160M, 160M2 motor graders, 627G, 637G wheel tractor scrapers, 814F II, 815F II, 816F II machines, 973C track loader, MD5075, MD5075C drills, TH31-C9P petroleum package, and CAT C9-based forestry and mobile hydraulic power units, reducing downtime for fleet operators and service workshops.

The injector supports accurate fuel delivery, reliable combustion, and stable engine operation under heavy load. For maximum service life, operators should use clean diesel fuel, replace fuel filters on schedule, drain the water separator regularly, inspect fuel lines for leaks or air entry, monitor oil condition for HEUI actuation pressure, read ECM fault codes, and test removed injectors on professional equipment to confirm flow, leakage, and response performance.