Usage:
3406B (2EK, 8TC),
3406B And 3406C (3ZJ, 4CK, 4MG, 5KJ, 7FB),
3406C (8PN) Truck Engines
As a result of changing emissions requirements, there have several designs of fuel injection pump check valves. The pump check valve is located in the bonnet and is responsible for maintaining stable hydraulic pressure during fuel injection. The different fuel injection pump check valves can be identified by the markings shown in the illustrations. The chart identifies the correct check valve to use each engine.
Illustration 1. 4P-9258 Valve Assembly, Punch mark on top.
Illustration 2. 115-5705 Valve Assembly, Identification marking on bottom face (some early production parts are marked on top).
Illustration 3. 4P-7688 Valve Assembly, Identification marking on bottom face (markings started in late 1994 production, earlier parts had no identification marking).