MDX V6-3.7L (2007)
Piston Ring: Service and Repair
Piston Ring Replacement
1. Remove the piston from the engine block.
2. Using a ring expander (A), remove the old piston rings (B).
3. Clean all the ring grooves thoroughly with a squared-off broken ring, or a ring groove cleaner with a blade to fit the piston grooves. File down the
blade, if necessary. The top ring and second ring grooves are 1.2 mm (0.05 in.) wide, and the oil ring groove is 2.8 mm (0.11 in.) wide. Do not
use a wire brush to clean the ring grooves, or cut the ring grooves deeper with the cleaning tool.
NOTE: If the piston is to be separated from the connecting rod, do not install new rings yet.
4. Using a piston, push a new ring (A) into the cylinder bore 15-20 mm (0.6-0.8 in.) from the bottom.
5. Measure the piston ring end-gap (B) with a feeler gauge:
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If the gap is too small, check to see if you have the proper rings for your engine.
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If the gap is too large, recheck the cylinder bore diameter against the wear limits.
Piston Ring End-Gap
Top Ring:
Standard (New): 0.30-0.40 mm (0.012-0.016 in.)
Service Limit: 0.60 mm (0.024 in.)
Second Ring:
Standard (New): 0.40-0.55 mm (0.016-0.022 in.)
Service Limit: 0.70 mm (0.028 in.)
Oil Ring:
Standard (New): 0.20-0.70 mm (0.008-0.028 in.)
Service Limit: 0.80 mm (0.031 in.)