fuel Fuel Injection Lines Kit with Clamp for CAT Caterpillar 3406 3406B 3406C 1917941 Posted on January 21, 2024 by admin 1 qty – #1 Fuel Line (OE # 7C3421, 4P9661, 1917941, 4P3921). Great Compatibility? Perfectly compatible with Caterpillar 3406, 3406B, 3406C, 980G, 980F, D8R, D8N, 826C, D400E. Note: This kit does not fit for 3406E engines. 3406b 3406c caterpillar clamp fuel injection lines