GM Tech Tip: Intake Manifold Inspection After Severe Internal Engine Damage – UnderhoodService

GM Tech Tip: Intake Manifold Inspection After Severe Internal Engine Damage

When replacing an engine due to internal damage, extreme care should be taken when transferring the intake manifold to the new engine long block. The internal engine damage may have resulted in the potential discharge of internal engine component debris into the intake manifold via broken pistons and/or bent, broken or missing intake valves.
Models: 
2014 and Prior GM Cars and Trucks 
After removing the intake manifold from the engine, the technician must carefully inspect all of the cylinder head intake ports to see if the valve heads are still present and not bent. Usually when the valve heads are missing or sufficiently bent, internal engine component debris will be present to varying degrees in the intake port of the cylinder head. If this debris is present in any of the cylinder head intake ports, the intake manifold should be replaced.
This replacement is required due to the complex inlet runner and plenum configuration of most of the intake manifolds. This makes thorough and complete component cleaning difficult and nearly impossible to verify the complete removal of debris.
Reinstallation of an intake manifold removed from an engine with deposits of internal engine component debris may result in the ingestion of any remaining debris into the new engine. This will cause damage or potential failure of the new engine long block.
Courtesy of MotoLOGIC® Repair & Diagnostics: www.motoshop.com/motologic.

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