12138 Mercruiser ROD, AUTOMATIC CHOKE

Sulfuric Acid Burn Hazard may cause serious personal injury or death.The exhaust gas cooler may contain a small amount of sulfuric acid. The use of fuel with sulfur levels greater than 15 ppm may increase the amount of sulfuric acid formed. The sulfuric acid may spill from the cooler during service of the engine. The sulfuric acid will burn the eyes, skin and clothing on contact. Always wear the appropriate personal protective equipment (PPE) that is noted on a material safety data sheet (MSDS) for sulfuric acid. Always follow the directions for first aid that are noted on a material safety data sheet (MSDS) for sulfuric acid.
Note: Plug and cap all open ports.
Illustration 1 g06454160
Typical Example
Disconnect connection (1) from breather heater (2). Loosen hose clamp (4). Remove inlet tube assembly (5) from turbo charger (3).
Illustration 2 g06476034
Follow Step 2a through Step 2k to remove Nitrogen oxide Reduction System (NRS) cooler (9) coolant hoses.
Make temporary marks on coolant hoses and clamps for installation purposes only.
Loosen hose clamp (6). Position the hose clamp away from connection (19).
Loosen hose clamp (8). Position the hose clamp away from NRS cooler assembly (9).
Remove hose (7) from connection (19) and NRS cooler assembly (9).
Use a suitable tool to compress hose clamp (18). Position the hose clamp away from water pump (17).
Use a suitable tool to compress hose clamp (15). Position the hose clamp away from the water temperature regulator housing.
Remove hose (16) from water pump (17) and the water temperature regulator housing.
Loosen hose clamp (13). Position the hose clamp away from connection (14).
Loosen hose clamp (11). Position the hose clamp away from Exhaust Gas Regulator (EGR) valve (12) (not shown).
Remove hose (10) from EGR valve (12) and connection (14).
If necessary, remove connection (14) from the engine cylinder block and connection (19) from the water pump.
Illustration 3 g06476064
Support tube assembly (25). Remove bolts (20) and bolts (24). Remove gasket (21) (not shown) and gasket (23) (not shown) from the tube assembly.Note: Discard the gaskets.
Disconnect harness assembly (22) from EGR valve (12). Position the harness assembly away from the EGR valve.
Illustration 4 g06454064
Remove bolt (26) from NRS cooler assembly (9).
Illustration 5 g06476089
Support NRS cooler assembly (9). Remove bolts (27) and bolts (29).
Remove EGR valve (12) from exhaust manifold (28). Discard gasket (30) (not shown).
Illustration 6 g06476022
If necessary, follow step 8a through step 8d to disassemble the exhaust cooler assembly (9).
Place the exhaust cooler assembly in a suitable support.
Remove bolts (31).
Remove exhaust cooler (9) from EGR valve (12).
Discard gasket (32) (not shown) and O-ring seal (33) (not shown).Installation Procedure
Table 1
Required Tools
Tool Part Number Part Description Qty
A - Anti-Seize Compound 1
B - Loctite 575 1
C - International Products P-80 Emulsion 1
Check all components for wear and damage. If necessary, replace any components that are worn or damaged.
Ensure that the exhaust cooler (NRS) assembly is free from restriction and external damage. Ensure that the exhaust cooler (NRS) assembly and tube assemblies are free from wear and damage. Refer to Systems Operation Testing and Adjusting, "Exhaust Cooler (NRS) - Test" for the correct inspection procedure.Note: Cleaning of the internal core of the exhaust cooler (NRS) should not be carried out.
Illustration 7 g06476027
If necessary, follow step 3a through step 3e to assemble the exhaust cooler assembly (9).
Place EGR valve (12) in a suitable support.
Install new O-ring seal (33) in Position (Y) in the EGR valve. Using Tooling (C), apply a small amount to the new O-r