3406E and 3456 Industrial Engines – Water Temperature Regulator & Manifold

Remove & Install Water Temperature Regulator & Manifold

Fluid Spillage Containment

Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting and repair of the machine. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids. Refer to “Tools And Shop Products Guide”, NENG2500 for tools and supplies suitable to collect and contain fluids in Caterpillar machines. Dispose of fluids according to local regulations and mandates.

1. Drain the coolant from the engine into a suitable container for storage or disposal.

2. Disconnect the upper hose from the water manifold.

3. Loosen hose clamps (2). Remove five bolts (1) and regulator housing (3).

4. Remove water temperature regulator (4) from housing (3).

5. Check the condition of lip-type seal (5). Use a new part for replacement if seal (5) is worn or damaged. Use Tool (A) to install a new seal (5). When installing seal (5), make sure that the seal is seated completely in the counterbore of housing (3).

6. Remove gasket (7) from water manifold (6). Do not reuse gasket (7).

7. Disconnect the wire and use Tool (B) to remove water temperature sensor (8) from manifold (6).

8. Remove three bolts (9) from water manifold (6).

9. Remove water manifold (6). Remove the O-ring seal and gasket from beneath water manifold (6).

NOTE: The following steps are for installing the water temperature regulator and manifold.


Make sure all surfaces are clean. Lubricate the seals and O-ring seals with clean engine oil before installation.

10. Put a new gasket and O-ring seal in position between the cylinder head assembly and manifold (6). Put clean engine oil on the O-ring seal.

11. Install and tighten bolts (9) to a torque of 50 ± 9 N·m (37 ± 7 lb ft).

12. Install a new gasket (7), water temperature regulator (4) and housing (3). Tighten bolts (1) to torque of 50 ± 9 N·m (37 ± 7 lb ft).

13. Position and tighten hose clamps (2) to a torque of 12 ± 3 N·m (15 ± 2 ft). Refer to the Specifications Module for further information.

14. Use Tool (B) to install water temperature sensor (8) and connect the wire. Tighten sensor (8) to a torque of 20 ± 3 N·m (15 ± 2 lb ft).

15. Connect the upper hose to the water manifold.

16. Fill the engine with coolant to the proper level. Refer to the Operation & Maintenance Manual for further information.