Operation CHARM: Car repair manuals for everyone.

Cylinder Bore Cleaning and Inspection

CLEANING

NOTE: If poor or improper cleaning procedures of the cylinder bores and/or cylinder block (6010) are followed, rusting may occur. Clean cylinder bore after any service operation such as honing or deglazing.
1. Clean the bore(s) with soap or detergent and water.
2. Then, thoroughly rinse the bore(s) with clean water to remove the soap or detergent.
3. Wipe the bore(s) with a clean lint-free cloth.
4. Finally, wipe the bore(s) with a clean cloth dipped in engine oil.

INSPECTION
Inspect For Cracks
After the cylinder block has been thoroughly cleaned check it for cracks. Inspect the cylinder block for cracks in the cylinder bores and between cylinders. If cracks are suspected that cannot be seen with the eye, there are magnetic and dye check inspection processes available through automotive machine shops. Tiny cracks not visible to the naked eye may be detected by coating the suspected area with a mixture of 25 percent kerosene and 75 percent light engine oil. Wipe the part dry and immediately apply a coating of zinc oxide dissolved in wood alcohol. Do not use rubbing alcohol as a substitute. If cracks are present, the coating will become discolored at the damaged area. Replace the cylinder block if it is cracked.

Inspect For Surface Irregularities
Check all machined surfaces for burrs, nicks, scratches and scores. Remove minor imperfections with an oil stone.

Cylinder Bore Diameter





^ Measure X and Y at the three levels shown.
^ The standard cylinder bore diameter is 90.220 mm (3.552 inch).

Check Cylinder Bore Taper





^ Subtract the cylinder bore diameters from points A and C as shown.
^ If the difference between measurements A and C exceeds the maximum taper value of 0.006 mm (0.000236 inch), rebore the cylinder bore to oversize.

Cylinder Out-Of-Round





^ Measure the cylinder bore diameters in two directions.
^ If the difference between measurements exceeds the maximum out-of-round specification, rebore the cylinder bore to oversize.
Maximum: 0.015 mm (0.000590 inch).
Service Limit: 0.020 mm (0.000787 inch).

Piston-To-Cylinder Bore Clearance

NOTE: Use the above measurements obtained at right angles (90°) to the engine centerline when calculating the piston-to-cylinder bore clearance.

1. Measure the diameter of each cylinder bore at the top, middle and bottom with the gauge placed at right angles to the centerline of the engine.
2. Subtract the piston diameter from these measurements.
Maximum Piston to Cylinder Bore clearance: 0.018-0.046 mm (0.000709-0.001811 inch).