TM-5-4310-347-14

SECTION XI

REPAIR AND OVERHAUL INSTRUCTIONS

AIR COMPRESSOR ASSEMBLY AND ELECTRIC MOTOR

COMPRESSOR REPAIR AND REPLACEMENT STANDARDS

Desired Clearance

Min.

Cylinders

Bore low - pressure

Bore high - pressure

Out of round .-

Taper

Crankshaft

Journal rod) die-

Taper

Out-of-round

End play

Pistons end Pins

1.370

Piston, low-pressure 4.619

Piston, high-pressure2.4965

Pin, low-pressure

Pin, high-pressure

Bearings, Connecting Rod

Bearing, id

Bearing, side clearance

4.6245

2.4995

2.125

2.125

.8125

Manufacturer’s dimensions and tolerances in inches

Max.

4.6255

2.5005

1.3765

4.620

2.4975

2.135

2.135

8130

0.010

A. PISTONS, PISTON RINGS, CONNECTING RODS,

AND CYLINDER BLOCK

1.

Removal and Dissembly.

a.

Remove the compressor assembly Section VIII,

C1.

b.

Refer to figure 16 and disassemble tube

assemblies, cooler tubes, manifolds and air cleaner a shown.

c.

Refer to figure 17 and remove hand hole plate.

d.

Refer to figure 18 and remove connecting rod

bearing caps

Min.

Max.

CAUTION: Mark the connecting rod from which the caps were removed, and reassemble caps on the same rod.

Do not inter-mix the connecting rods and cap.

e.

f.

Disassemble cylinder block from crankcase as

shown in figure 17.

Dissemble connecting rods, pistons and rings as

shown in figure 18.

NOTE: Mark connecting rod and piston to assure correct relationship at reassembly.

NOTE: Do not remove the connecting rod bushings unless inspection reveal them defective.

Maximum allowable wear amd clearance

0.004

0.002

0.001

0.001

0.001

0.005

0.000

0.003

0.0015

0.0001

0.0001

0.001

0.017

0.002

0.005

0.0035

0.0005

0.0005

0.007

0.006

0.003

2.

Cleaning, Inspection and Repair.

a.

Clean all parts with an approved cleaning solvent and dry thoroughly.

b.

Inspect the cylinder block for broken cooling fins and cracks. Inspect the cylinder bore for wear, scoring, pitting, or other damage. Replace the block if defective.

c.

Measure the clearance of the piston pin to the piston pin bushing. Check for proper fit. Aline or replace, connecting rods, if necessary.

d.

Place the piston rings in the cylinder bore with the piston ring square in the cylinder bore about

1/2 inch from the top.

e.

If the ring gap is less than the specified width, file across but ends of the rings to increase the gap to, the required tolerance. If the ring gap is greater than required, replace the entire set of rings.

f.

Measure the ring groove in the piston for wear.

Replace pistons if necessary.

3. Reassembly and Installation.

a. Refer to figures 16, 17, and 18 and re assemble.

and install the pistons, piston rings, connecting rods and cylinder block taking the following precautions:

1.

If new connecting rod bushings are to be installed, and are not prefit, ream the bushings.

2.

When installing piston rings expand them carefully and sufficiently to allow the ring to

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1. Crankcase

2. Plate, hand hole

3. Gasket, hand hole plate

4. Screw, cap

S. Plug, pipe

6. Seal, oil

7. Plug, pip:

8. Nipple, pipe

9. Cap, pipe

10. Gauge,, oil level

11. Flywheel

12. Key

13: Bolt, machine

14. Nut, hex

15. Gasket set

16. Fitting, compression

17. Housing governor

18. Plate, baffle

19. Gasket, governor cover

20. Spindle, governor

21. Pin, spring

22. Washer, spring lock

23. Screw, cap

24. Washer, flat

25. Spring governor main

26. Sleeve, spring

27. Screw, cap

28. Weight, governor

29. Cover, governor housing

30. Kit, release valve assembly

31. Plunger, release valve

32. Ball, release valve

33. Spring, release valve

34. Body, release valve

35. Elbow, 900

36. Screw, machine

S37. Muffler assembly, unloader

38. Body, unloader muffler

39. Felt

40. Screen

41. Gasket, cylinder flange

42. Cylinder

43. Screw, cap

Figure 17. Crank Case and unloader assembly, exploded view.

18

1. Kit connecting rod assembly L.P.

2. Kit connecting rod assembly H.P.

3. Rod, connecting w/bolt L.P.

4. Rod, connecting w/bolt H.P.

5. Bearing, piston pin

6. Bolt, connecting rod

7. Dipper, oil H.P.

8. Dipper, oil L.P.

9. Kit, piston assembly H.P.

10. Kit, piston assembly L.P.

11. Ring, piston pin retaining

12. Pin, piston

13. Piston, high pressure

14. Ring set, H.P. piston

15. Piston, low pressure

16. Ring set, L.P. piston

17. Assembly, main bearing

18. Cup, bearing,

19. Cone & roller, bearing

20. Crankshaft

Figure 18. Crankshaft, piston and connecting rod assemblies, exploded view.

to slide freely over the piston to the proper position. Starting with the bottom ring, install piston rings in their proper grooves

Stagger ring gaps so that they are not lined up.

3.

Lubricate each piston and connecting rod assembly with a light cost of engine oil before installing in cylinder block.

Compress the piston rings carefully when installing in cylinder.

4.

When installing cylinder block to crankcase always use new flange gasket and torque nuts to 45 ft.-lbs. torque.

5.

Torque connecting rod nuts to 25 ft.-lbs.

torque.

B. CRANKSHAFT AND CRANKCASE

1.

Removal and Disassembly.

a.

Refer to figure 7 and remove the unloader

assembly.

b.

Remove the hand hole plate and flywheel.

c.

Remove bearing caps (figure 18) and push

connecting rods and pistons up to the top of the cylinder bore. Remove the cap screws that secure unloader housing to crankcase.

d.

Drive the crankshaft, bearings, and unloader housing from the crankcase.

CAUTION: Before driving the crankshaft from the crankcase, be sure the connecting rod journals are in an upright position.

e. Using suitable puller remove the unloader housing and bearing from the shaft.

f.

Remove the oil seal from the crankcase.

NOTE: Do not remove the oil level gage from the crankcase unless the gage is leaking or defective.

19

1. Body assembly

2. Stator wedge kit

3. Bracket, front

4. Bracket, rear

5. Rotor assembly

6. Bolt, stud

7. Bearing

8. Flinger, external

9. Key

10. Shaft L

11. Conduit box assembly

12. Bearing

13. Spring, loading

14. Flinger, external

15. Fan, external

16. Nut

17. Cover, fan

18. Fan

Figure 19. Electric motor assembly.

2.

Cleaning, Inspection, and Repair.

a.

Clean all parts in an approved cleaning solvent and dry thoroughly.

b.

Inspect the crankshaft for cracks, scores, and distortion Measure the crankshaft journals for wear. If the connecting rod journals measure

0.0005 inch out-of-round, replace the.

crankshaft.

c.

Inspect the crankshaft bearings for rough, pitted, or scored rollers. Replace a defective hearing.

d.

Inspect the crankcase for cracks, breaks or other defects. Replace the crankcase if defective.

3.

Reassembly and Installation., a.

Refer to figures 17 and 18 reassemble and

install cry shaft in crankcase using the following procedures:

1.

Always install new oil seal in crankcase.

2. Press bearing cup in the unloader housing.

3. Install new gasket on the unloader homing.

C. ELECTRIC MOTOR

1.

Removal and Disassembly.

a.

Remove the electric motor, Section VIII, B1.

b.

Refer to figure 19 and disassemble electric

motor.

2.

Cleaning, Inspection, and Repair.

a.

Clean all parts with an approved cleaning solvent and dry thoroughly.

b.

Inspect all parts for wear or damage and replace worn defective part

3.

Reassembly and Installation.

a.

Refer to figure 19 and reassemble the electric

motor.

b.

Install the electric motor, Section VIII, B2.

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