Figure 5-143. Checking breaking torque of cylinder base nuts, using box wrench-5120-678-5287.

Note. Before removing cylinder assemblies, it

will be necessary to check the breaking torque of

t h e 14 nuts attaching each cylinder assembly to

crankcase assembly. This check is necessary to

Note. Before removing each cylinder

determine whether base nut stud has stretched.

assembly, the crankshaft must be turned to

All stretched studs must be replaced.

p o s i t i o n the piston of the cylinder being removed

to top dead renter. Rotate crankshaft using

1. Check breaking torque of the 14 nuts (B) securing

splined

wrench

-5120-793-7895

(fig.

5-91)

and

cylinder assembly to crankcase assembly using box

observe when (connecting rod has raised piston to

wrench

(A)-5120-678-5287

combination

with

torque wrench. When torque required to break a nut

top dead center. Make certain each piston is

loose is less than 600 pound inches, remove nut, apply

properly positioned before attempting cylinder

antiseize compound FSN 9150-663-1770 to stud,

removal.

install nut and tighten to a torque of 600 to 660 pound

inches. When nut does not tighten to the recommended

1. With right bank cylinder assemblies in a vertical

torque, stud is stretching and must be replaced, Mark

(upright) position remove the remaining two nuts (A)

stud for replacement. Refer to paragraph 6-4e for

from each right cylinder assembly. Make certain each

instructions on replacement of studs.

piston is positioned at top dead center before at-

2. After checking the breaking torque, remove all nuts

tempting removal.

(B) except one on each side of cylinder. The remaining

2. Do not remove the nuts (B) holding the left cylinder

two nuts are removed after piston has been positioned

assemblies to crankcase until left cylinders have been

to top dead center for removal (fig. 5-144).

rotated to an upright position for removal.

Figure 5-143. Checking breaking torque of

Figure 5-144. Right bank cylinders in vertical

cylinder base nuts, using box

position for removing or installing

wrench-5120-678-5287.

cylinders from crankcase.

5-80