LOCKNUT 1293180 - Caterpillar

3406C, 3408C, And 3412C Diesel Industrial, Marine, And Generator Set EnginesReference: Engine News, April 1994, Page 1, "Identification Of Intake and Exhaust Valves That May be Used In Remanufactured Direct Injected 3400 Cylinder Heads". Description of Change: New intake and exhaust valves are used in these engines. The new valves have chrome plated stems that provide a harder, slicker surface. This extends the valve life by resisting sticking. The chrome plated stems also promote precise valve actuation which reduces valve head stress and minimizes deposit build-up. Adaptable To: The new 108-5902 Intake Valve and 106-1111 Exhaust Valve are direct replacements for the former 2W-2622 Intake Valve and 1W-3860 Exhaust Valve. Remanufactured Cylinder Heads
The Reference article contained part numbers of valves used in remanufactured direct injection cylinder heads. Beginning in February 1994, remanufactured cylinder heads contain only the 108-5902 Inlet and 106-1111 Exhaust Valves.