Standards and Service Limits

Engine Block:

Engine Block


Cylinder-to-Piston Clearance








Calculate the difference between cylinder bore diameter and piston diameter. If the clearance is near or exceeds the service limit, inspect the piston and cylinder bore for excessive wear.


Main Bearing Selection
Crankshaft Bore Code Location








Letters or bars have been stamped on the end of the block as a code for the size of each of the four main journal bores. Use them, and the numbers stamped on the crankshaft (codes for main journal size), to choose the correct bearings. If the codes are indecipherable because of an accumulation of dirt and dust, do not scrub them with a wire brush or scraper, Clean them only with solvent or detergent.