PISTON FIT

ENGINE

6. Cross hatches should be clearly visible after

2. Drain the crankcase and remove the oil pan.

glaze

breaking

operations.

3. Remove capscrews from the connecting rods,

permitting removal of caps. Keep the caps and bolts in

numerical order so that when the pistons and rods are

removed from the engine, the cap can be reassembled

and kept with its mating part. If not already numbered,

do so at this time.

4. Push the pistons and connecting rods up

through the top of the cylinders.

5. Cut the glaze on the cylinder bores with a de-

glazer to assure quick seating of the new piston rings.

(Fig. 23) Protect the crankshaft with oily (not dirty) rags

during the deglazing operation.

NOTE:

The de-glazer, fitted with 220 grit

Figure 24.

stones, may be run up and down the

cylinder bore while being turned with

B. PISTON FIT

an electric drill until the shiny

surface (glaze) is removed. These

1. Check the piston fit in the bore using a half-inch

surfaces must then be throughly

wide strip of .003 inch feeler stock attached to a small

cleaned by wiping with a clean, oiled

scale of approximately 15 lbs. capacity.

rag which will pick up the small

particles. of dust that are embedded

2. Insert the feeler between the piston and the

in the pores of the iron.

cylinder, midway between the piston pin bosses. When

the correct fit is obtained, a pull of 5-10 pounds on the

scale will be needed to withdraw the feeler. (Fig. 25)

The pistons must be fitted with the block and pistons at

room temperature (6870 ).

- F

Figure 23.

Figure 25.

B-8