ASE A1 Engine RepairEngine Block AssemblyMedium
A technician is performing a pre-assembly inspection of an engine block. They observe an area on the cylinder wall just below the deck surface that is significantly worn, forming a 'ridge.' Which of the following is the MOST appropriate action to take before reassembly?
- AHone the cylinder bore to remove the ridge
- BReam the cylinder ridge before piston removal/installation
- CInstall new, oversized piston rings
- DApply a thicker head gasket to compensate
Show answer & explanationAnswer & explanation
Correct answer: B. Ream the cylinder ridge before piston removal/installation
A cylinder ridge forms at the top of the cylinder bore due to piston ring wear. This ridge must be reamed or cut out before attempting to remove or install pistons to prevent damage to the piston or rings.
Why the other options are wrong
- A. Honing removes material from the entire bore but typically isn't sufficient for a significant ridge, and the ridge must be removed before honing if present.
- C. Installing oversized piston rings would not address the ridge and could cause damage.
- D. Applying a thicker head gasket would not address a cylinder ridge and is unrelated to cylinder bore condition.
Cylinder Ridge Reaming
The process of removing the wear ridge that forms at the top of a cylinder bore to allow safe removal and installation of pistons and rings.
- Prevents piston/ring damage
- Located at top of cylinder travel
- Performed with a ridge reamer tool
Memory trick: Ridge removal, smooth install, no piston fall.