GM Service Manual Online
For 1990-2009 cars only

Tools Required

SA9171E Flex Hone

    Caution: Do not allow hone to come out of the cylinder bore while it is turning. The stones could be released and cause injury.

  1. Bore cylinders to within 0.005 mm (0.0002 in) of desired size using 120-150 grit stones.
  2. Finish hone to desired size by removing 0.005 mm (0.0002 in) left in the following second step using 320 grit stones.
  3. Refer to Piston Selection for the correct size piston to use for each cylinder.


    Object Number: 871167  Size: SH

    Important: Make sure the crankshaft pulley/damper keyway is at the 3 or 9 o'clock position to prevent damage of the crankshaft connecting rod journals during honing.

  4. Hone the cylinder bore using a 10W-30 or 5W-30 weight motor oil and the SA9171E .
  5. Make sure the flex hone is slowly rotating upon entry and removal from the cylinder bore.
  6. Important: The recommended speed of the flex hone is 150-200 RPM. Do not use air pressure driven or high-speed tools.

  7. Use 60 strokes per minute. Honing time should be approximately 20 seconds or 20 strokes per cylinder to develop a 45-50 degree, included angle, honing cross-hatch. One stroke consists of a full downward and upward motion of the flex hone in the cylinder bore.
  8. Thoroughly scrub the cylinder bores after honing with a scrub brush, a strong solution of hot water and Tide® powder laundry detergent, or equivalent. Thoroughly rinse with hot clean water, high-pressure if available.
  9. Important: If the cylinder bores are not thoroughly cleaned, the residual grit from the honing stones will wear out the piston rings and the cylinder bores extremely fast, resulting in oil consumption. Never use solvent to clean cylinder bores. It will only redistribute the grit on the cylinder walls. Detergent and hot water will carry the grit away.

  10. Dry the cylinder bores and wipe them with a clean white towel saturated with engine oil. Dark residual grit on the towel after wiping the cylinder bore indicates the bores are not clean. The cleaning process in step 6 must be repeated until the towel is free of all dark residual grit.