Caterpillar original Diesel Fuel Injector 166-0151 Nozzle for C12 Engine 345B II 365B L, Replacement for 170-5252 187-6549 10R-0967 10R-1258 10R-1003 212-3463 original new injector

The CAT C12 diesel fuel injector 166-0151 is an original replacement injector engineered for Caterpillar C12 heavy-duty diesel engines used in trucks, construction equipment, mining support equipment, industrial power units, and diesel generator sets. Designed as a direct OE-style replacement, it delivers precision fuel delivery through an optimized spray pattern, supported by wear-resistant hardened components and consistent build quality. Multiple cross-reference numbers—including 350-7555, 170-5252, 147-0373, 161-1785, 166-0149, 187-6549, 212-3462, 212-3463, 229-1631, 10R-0961, 10R0961, EX630961, 116-5426, and 213-3465—simplify procurement and inventory management for fleet operators, rebuild shops, and distributors.

This injector supports stable engine performance by improving combustion efficiency and maintaining consistent fuel metering across demanding duty cycles. Operators benefit from reduced downtime, easier installation, and predictable repair outcomes when matched to confirmed C12 engine serial numbers, arrangement numbers, and original injector specifications. It is suited to both single-unit replacement and matched set replacement during engine overhaul programs.

Proper maintenance extends injector service life and protects the fuel system. Best practices include using clean diesel fuel, replacing fuel filters on schedule, draining water separators, monitoring engine oil condition, scanning ECM fault codes, inspecting for leaks and wiring damage, and performing injector balance or return flow testing when symptoms such as hard starting, rough idle, power loss, excessive smoke, or elevated fuel consumption appear.