5-43. CYLINDER BLOCK-MAINTENANCE INSTRUCTIONS (Continued).
Before attempting to check the block bores, hone them throughout their entire
length until about 75% of the area above the ports has been cleaned-up.
Hone the block bores as follows:
(1) Use a hone in which the cutting radius of the stones can be set in a fixed position
to remove irregularities in the bore rather than following the irregularities as with a
spring-loaded hone. Clean the stones frequently with a wire brush to prevent stone
loading. Follow the hone manufacturer' s instructionsregarding the use of oil or
kerosene on the stones. Do not use such cutting agents with a dry hone. Use 120
(2) Insert the hone in the bore and adjust the stones snugly to the narrowest section.
When correctly adjusted, the hone will not shake in the bore, but will drag freely
up and down the bore when the hone is not running.
(3) Start the hone and '"feel out" the bore for high spots which will cause an increased
drag on the stones. Move the hone up and down the bore wit short, overlapping
strokes about 1 inch (2.54 cm) long. Concentrate on the high spots in the first cut.
As these are removed, the drag on the hone will become lighter and smoother. Do
not hone as long at the air inlet port area as in the rest of the bore because this
area, as a rule, cuts away more rapidly. Feed lightly to avoid an excessive
increase in the bore diameter. Some stones cut rapidly even under low tension.