FUEL TRANSFER PUMP GROUP 5M7625 - Caterpillar

3406B (6TB, 4TB, 2WB, 3SF, 4RG);
3412 (9XF) EnginesReference: Service Magazine; December 1, 1986; Page 11; "Improved Retaining Bushing In Fuel Injection Pump" for 3406B...2WB, 4TB, 6TB, 7FB, 70V Engines.Description of Change: A phosphate coating permits the fuel injection pump bushing to be tightened to a higher torque. The increase in torque reduces leakage at the joint between the plunger and barrel assembly. Previously, the bushing was tightened to a torque of 230 15 N m (170 10 lb ft). This could allow the bushing to leak. Typical symptoms may include possible misfire, low power, and poor fuel economy.Adaptable To: The phosphate coated 7C6617 Bushing is a direct replacement for the former anodized coated 8N0656 Bushing used in the improved 2W3413 Fuel Injection Pump Group. To differentiate between the two bushing types, the improved phosphate coated bushing appears flat black or charcoal in color prior to painting, while the former anodized bushing is a shiny gold color. Tighten the 7C6617 Bushing to a torque of 245 15 N m (180 10 lb ft).
Illustration 1. Typical fuel injection pump location.
Illustration 2. (1) 7C6617 Bushing. (2) 2W3414 Plunger & Barrel Assembly.