Piston, Ring, Pin, and Connecting Rod Inspection: Inspection

How to use this manual .

1. Piston Ring End Gap - Inspect

   Preconditions 

   • Piston Rings Removed

   Procedure/Specifications 

   1. Using a piston that has its rings removed, push a new ring (a) into the cylinder bore.

   Measurement Position 

   Standard Value
   b	15-20 mm (0.59-0.79 in)

   Courtesy of HONDA, U.S.A., INC.

   2. Measure the ring end-gap (c) with a feeler gauge.

   Specifications 

   	Object	Standard Value (New)	Service Limit
   c	Top Ring	0.20-0.23 mm (0.008-0.009 in)	0.23 mm (0.009 in)
   	Second Ring	0.40-0.52 mm (0.016-0.021 in)	0.52 mm (0.021 in)
   	Oil Ring	0.32-0.58 mm (0.013-0.022 in)	0.58 mm (0.022 in)

   Result 

   • If the gap is too small, check to see if you have the proper rings for your engine.
   • If the gap is too large, recheck the cylinder bore diameter against the wear limits - Refer to: Block and Piston Inspection ()  or Cylinder Bore Honing () .
2. Piston Pin - Inspect

   Preconditions 

   • Piston Pin Removed

   Courtesy of HONDA, U.S.A., INC.

   Procedure/Specifications 

   • Measure the diameter of the piston pin.

   Tool Details 

   Name
   a	Micrometer

   Specifications 

   Object	Standard Value (New)	Service Limit
   Piston Pin	21.962-21.965 mm (0.86464-0.86476 in)	21.954 mm (0.86433 in)

   Result 

   • If the measurement is not within specifications, replace the piston pin.
3. Piston Pin-to-Piston Clearance - Inspect

   Preconditions 

   • Piston Pin Removed
   • Piston Pin Normal Condition

   Figure 1 

   Courtesy of HONDA, U.S.A., INC.

   Procedure/Specifications 

   1. Measure the diameter of the pin.

   2. Zero the dial indicator (a) to the pin diameter. (Figure 1)

   Tool Details (Figure 1) 

   Name
   a	Dial Indicator

   Figure 2 

   Courtesy of HONDA, U.S.A., INC.

   3. Check the difference between the pin diameter and the pin hole diameter in the piston. (Figure 2)

   Specifications 

   Standard Value (New)	Service Limit
   -0.005-0.002- mm (-0.00020-0.00008 in)	0.012 mm (0.00047 in)

   Result 

   • If the measurement is not within specifications, replace the piston .
4. Piston Pin-to-Connecting Rod Clearance - Inspect

   Preconditions 

   • Piston Pin Removed
   • Piston Pin Normal Condition

   Figure 1 

   Courtesy of HONDA, U.S.A., INC.

   Procedure/Specifications 

   1. Measure the diameter of the pin.

   2. Zero the dial indicator (a) to the pin diameter. (Figure 1)

   Tool Details (Figure 1) 

   Name
   a	Dial Indicator

   Figure 2 

   Courtesy of HONDA, U.S.A., INC.

   3. Measure the pin-to-rod clearance. (Figure 2)

   Specifications 

   Standard Value (New)	Service Limit
   0.005-0.015 mm (0.00020-0.00059 in)	0.019 mm (0.00075 in)

   Result 

   • If the measurement is not within specifications, replace the connecting rod .
5. Ring-to-Groove Clearance - Inspect

   Preconditions 

   • Piston/Connecting Rod Assembly Removed (Piston Ring Installed)

   Courtesy of HONDA, U.S.A., INC.

   Procedure/Specifications 

   • After installing a new set of rings, measure the ring-to- groove clearances.

   Tool Details 

   Name
   a	Feeler Gauge

   Specifications 

   Object	Standard Value (New)	Service Limit
   Top Ring	0.065-0.090 mm (0.003 in)	0.120 mm (0.005 in)
   Second Ring	0.030-0.055 mm (0.001-0.002 in)	0.085 mm (0.003 in)

   Result 

   • If the measurement is not within specifications, replace the piston.