Operation CHARM: Car repair manuals for everyone.

30. Engine Block Clean and Inspect

Engine Block Cleaning and Inspection
^ Tools Required
- J 8087 Cylinder Bore Gage
- J 42385-100 Head/Main Bolt Thread Repair Kit





1. Clean the following areas:

Notice: Do not use a caustic solution to clean the aluminum engine block.

Important: When cleaning an engine block in a thermal type oven, do not exceed 232°C (450°F).
^ The engine block in the solvent
Remove all sludge, dirt, or debris.

Caution: Refer to Safety Glasses Caution in Service Precautions.

^ Dry the block with compressed air.
^ The gasket surfaces

^ The coolant passages
^ The oil galleries
^ The main bearing caps
^ The engine block head bolt holes for threadlocking material
Thread repair tool J 42385-107 may be used to clean the threads of old threadlocking material.
2. Inspect the following areas:
^ The cylinder walls for excessive scratches, gouging, or ring ridge
^ The coolant jacket for cracks
^ The valve lifter bores for excessive scoring or wear
^ The crankshaft bearing webs for cracks
^ The gasket sealing surfaces for excessive scratches or gouging

^ The oil galleries for restrictions
^ All threaded bolt holes for damage
3. Measure the following areas:
^ The cylinder bores for taper
^ The cylinder bores for excessive ring ridge at the top of the cylinder

Measuring the Cylinder for Taper, Out-of-Round, and Oversize
1. Adjust the micrometer to 99.0 mm (3.897 inch).
2. Insert the J 8087 into the micrometer and zero the bore gauge dial.





3. Use a bore gage and measure the cylinder bore for taper, out-of-round, and oversize.

Slide the bore gage up and down throughout the length of the cylinder bore. Check the bore both parallel and perpendicular to the centerline of the crankshaft.

A cylinder that measures 99.0-99.018 mm (3.897-3.898 inch) may be honed and serviced with a standard size piston.

A cylinder bore that exceeds the maximum diameter must be serviced with an oversized piston.