Initial Inspection and Diagnostic Overview

INSPECTION





Inspect the cylinder bores for damage or excessive wear.

Measure the cylinder bores.

Diameter mm in
MIN 102.000 4.0157
MAX 102.116 4.0203

Out-of-Roundness: 0.038mm [0.0015 inch]
Taper: 0.76mm [0.003 inch]

NOTE: Oversize pistons and rings are available for re-bored cylinder blocks.





The distortion of the combustion deck face in not to exceed 0.010mm [0.0004 inch] in any 50.00mm [2.0 inch] diameter.

Overall variation end to end or side to side 0.075mm [0.003 inch].

If the surface exceeds the limit, refer to the Alternative Repair section. Service and Repair





Inspect the main bearing bores for damage or abnormal wear.

If required, install the main bearings and measure main bearing bore diameter with main bolts tightened to 176 N-m [130 ft-lbs]. Record the measurement for later reference.

Standard Bearing Diameter
MAX 83.106 mm [3.2719 inch]





Inspect the camshaft bores for scoring or excessive wear.

Measure the camshaft bores. The limit for the No.1 bore applies to the ID of the bushing.

Diameter
MAX 54.133 mm [2.1312 in]

NOTE: If a bore exceeds the limit, refer to Alternative Repair Section.





Inspect the tappet bores for scoring or excessive wear.

Diameter
MAX 16.055mm [0.632 in]

CYLINDER BORES - DE-GLAZE





Note: New piston rings may not seat in glazed cylinder bores.

Deglazing gives the bore the correct surface finish required to seat the rings. The size of the bore is not changed by proper de-glazing.

Note: Completely disassemble engine before de-glazing cylinders.





Cover the lube holes In the top of the block with waterproof tape.





A correctly de-glazed surface will have a crosshatch appearance with the lines at 15 to 25 degree angles with the top of the cylinder block. 30 to 50 degrees indicates angles on crosshatch.





Use a drill, a fine grit Flexi-Hone and a mixture of equal parts of mineral spirits and SAE 30W engine oil to de-glaze the bores.





The crosshatch angle is a function of drill speed and how fast the hone is moved vertically.





This illustration shows the results of the drill speed too slow or the vertical stroke too fast.




This illustration shows the result of the drill speed too fast or the vertical stroke too slow.





NOTE: Vertical strokes MUST be smooth continuous passes along the full length of the bore.

Inspect the bore after 10 strokes.





Use a strong solution of hot water and laundry detergent to clean the bores.

Since a large volume of water must be used to rinse the bores, position the block over or close to a floor drain.





CAUTION: Clean the cylinder bores immediately after de-glazing.

Rinse the bores until the detergent is removed and blow the block dry with compressed air.





CAUTION: Be sure to remove the tape covering the lube holes after the cleaning process is complete.

Check the bore cleanliness by wiping with a white, lint free, lightly oiled cloth. if grit residue is still present, repeat the cleaning process until all residue is removed. Wash the bores and the complete block assembly with solvent and dry with compressed air.





Remove the protective tape from the block surface.