Flywheel and Flywheel Housing - TM-5-4320-258-340050

TM 5-4320-258-34

to the crankshaft, using the starting jaw (1) and collar

(2).

(3) Install the governor on the engine (TM

5-4320-258-12). Time the magneto (TM 5-4320-258-

12).

4-9.

Flywheel and Flywheel Housing

a. Removal.

Remove the flywheel and

flywheel housing as follows:

(1) Remove the six nuts (5, fig. 4-14) and

lock washers (6) that secure the flywheel (7) and ring

gear (8) to the crankshaft (40); remove the flywheel.

(2) Remove the cap screws (11, fig. 4-22),

shoulder screws (13), and lock washers (12 and 14) that

secure the flywheel housing (15) to the block (35);

remove the flywheel housing and gasket.

b. Cleaning, Inspection, and Repair.

(1) Clean the flywheel and flywheel

housing with cleaning solvent (FED. Spec. P-D-680);

dry thoroughly.

(2) Inspect the flywheel housing for cracks,

Figure 4-10. Checking flywheel runout.

distortion, and damaged threads; replace a damaged

flywheel housing.

(4) Check flywheel eccentricity by

(3) Inspect the flywheel for chipped,

mounting a dial indicator so that it indicates the inside

cracked, or broken teeth on the ring gear, distortion,

diameter of the flywheel counterbore (fig. 4-11); rotate

worn or out-of-round bolt holes, and other damage. If

the crankshaft through one revolution. If the flywheel is

the ring gear is damaged, replace as follows:

eccentric more than 0.008 inch, loosen and retighten the

Caution: When cutting the ring gear, be

flywheel mounting bolts and recheck eccentricity. If

extremely careful not to damage the flywheel.

eccentricity still exceeds 0.008 inch, replace the

(a) Cut the ring gear with a torch or

flywheel.

hack saw and remove the ring gear from the flywheel.

(b) Heat the replacement ring gear in

an oven and cool the flywheel in water or in a

refrigerator.

on the flywheel. As the ring gear and flywheel approach

the same temperature, the ring gear will contract to a

tight fit on the flywheel.

c. Installation.

(1) Position the flywheel housing (15, fig.

4-22) on the block (35); secure with shoulder screws

(13), cap screws (11), and lock washers (12 and 14).

(2) Position the flywheel (7, fig. 4-14) on

the crankshaft (40); secure with six bolts (9), lock

washers (6), and nuts (5). Tighten the nuts to 35 to 40

foot-pounds torque.

(3) Check flywheel runout by mounting a

dial indicator so that it indicates the flat vertical surface

of the flywheel (figure 4-10); rotate the crankshaft

through one full revolution. Hold pressure against the

flywheel to eliminate crankshaft end play. If flywheel

Figure 4-11. Checking flywheel eccentricity.

runout exceeds 0.008 inch, remove the flywheel and

clean the crankshaft flange and flywheel seat. Install

the flywheel and recheck runout. If runout still exceeds

(5) Check runout of the flywheel housing

0.008 inch, replace the flywheel.

face by mounting a dial indicator so that it indicates the

housing face (fig. 4-12); rotate the crankshaft through

one revolution. Hold pressure against the flywheel to

eliminate end play. If runout exceeds

4-17