Cleaning and Inspection - TM-9-2815-200-350330

Crankshaft.

Remove crankshaft oil

dye check method. Pay particular attention to

retaining plugs following instructions which

areas around crankshaft oil holes and fillets

accompany figure 6-33.

adjacent to the crank cheeks.

(2) Inspect connecting rod journal radii of

crankshaft for evidence of specific points of wear

or damages that would indicate a bent or twisted

connecting rod.

(3) Check diameters of main bearing and

connecting rod journals against limits specified

in overhaul standards (table 6-9). Check run-out

of crankshaft by supporting end journals in "V"

blocks and measuring the run-out at the center

journals with a dial indicator. Maximum

allowable run-out is 0.025 inch at No. 4 journal.

(4) Inspect journals for nicks, burs, grooves.

scratches, galling, scuffing, or discoloration.

Mark minor defect areas for future repair.

(5) Check dowel pins and straight pins for

tightness in the crankshaft flanges. Check pins

against limits specified in the overhaul standards

Remove

(table 6-9).

1. Remove six cotter pins (A).

Inspection

Connecting

Rods

and

2. Remove six bolts (B), slotted nuts, and flat washers.

Bearings.

3. Remove 12 retaining plugs (C) from each end of the

(1)

Connecting

rod

bearings. I n s p e c t

bore through the six crankshaft connecting rod jour-

nals.

connecting rod bearing halves (fig. 6-31) in the

Install

same manner as described for main sleeve

1. position 12 retaining plugs (C) in each end of the bore

bearings. Apply a thin coating of Prussian blue,

through the six crankshaft connecting rod journals.

FSN 8010-247-8706, to the backs of the con-

2. Install six bolts (B), slotted nuts, and flat washers

necting r o d b e a r i n g s a n d

install in

their

securing plugs.

3. Install six cotter pins (A) securing slotted nuts.

respective connecting rods and caps according to

Figure 6-33. Removing or installing crank-

the location markings (fig. 6-31). Assemble rod

shaft oil retaining plugs.

and cap, and torque tighten nuts to 950-pound-

inches. Check bearing inside diameter, using a

Note. Do not remove dowel pins (18, fig. B-3)

dial indicator as shown in figure 6-34, against

and straight pins (25) from crankshaft unless

the limits specified in the overhaul standards

inspection (para 6-16) indicates replacement is

(table 6-9) for contact as shown by Prussian

necessary.

Dowel

pins

flywheel

end

are

blue, FSN 8010-247-8706, transfer in the same

secured

with

setscrews.

manner in which the main sleeve bearings were

checked (para 6-9d). Replace any bearing that

6-16. Cleaning and Inspection

does not make at least 75 percent contact.

a. Cleaning. Refer to paragraph 6-2. Clean

(2) C o n n e c t i n g r o d a s s e m b l y .

crankshaft oil passages with compressed air and

(a) Check connecting rod bearing bore with

brass wire probes.

dial indicator against limits specified in

Note. Care must be taken not to destroy or

overhaul standards (table 6-9).

rod bearing

remove main and

connecting

(b) Check rods for cracks and for twisted or

location markings.

bent condition. Bent or twisted connecting rods

b. Inspection of Crankshaft.

must be replaced. Under no circumstances

with

(1) Inspect crankshaft for

cracks

should connecting rods be straightened. Destroy

magnetic

particle

inspection equipment or

any rod found damaged to insure it will not be

When

when

available.

similar

equipment

reused in an engine.

magnetic particle inspection equipment is not

available use a magnifying glass (five power

counterbore and contour areas (fig. 6-35). Mark

magnification minimum) and a strong light or

rods having sharp corners for repair.

6-36