Page 148 - REPOWER REFERENCE GUIDE (2020)

Exhaust System
Exhaust System Components

Anytime a longblock is to be replaced, exhaust system components must be inspected and replaced if they are worn or leaking.
Neglecting to do so can allow water to enter the cylinders, damaging the engine as soon as it is started.
Inspection of exhaust system components:
1. Visually inspect the exterior of the manifold, riser, and elbow for indication of external leaks.
2. Disassemble the riser (if equipped) and elbow from the manifold to inspect for gasket leaks.
3. Determine if gasket surfaces are resealable. (Refer to the appropriate Exhaust System Cleaning and Inspection section
for specifications.)
4. Leak test the water jacket of exhaust components for internal leaks.
5. Clean and paint as required.
6. Select the correct gaskets based on the engine cooling system.
7. Reassemble risers (if required) and elbow.
8. Ensure that all specifications for sealants and all torque requirements are met.

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