TM-9-2815-220-24

AVDS-1790 2CA, 2DA and 2DR Air-Cooled 12-Cylinder Diesel Engines

TECHNICAL MANUAL; UNIT, DIRECT SUPPORT AND GENERAL SUPPORT MAINTENANCE MANUAL FOR AVDS-1790 2CA, 2DA and 2DR Air-Cooled 12-Cylinder Diesel Engines

TM-9-2815-220-24 - Page 1232 of 1563

TM 9-2815-220-24

CYLINDER VALVES AND ASSOCIATED PARTS REPAIR

0145 00

REPAIR

1. Discard valves (intake or exhaust) that do not conform to the limits specified under inspection

(faces are badly warped, cracked, pitted, or burned; stems or locking grooves are badly pitted,

scored, or scratched).

2. Reface slightly pitted or burned valves (1 and 2) that do not have 360° of contact revealed at

inspection.

Reface to specifications (A through F) in the following table.

3. Recheck refaced valves (1 and 2) for 360° contact (repeat inspection steps 5 and 6).

4. Check valve length (G and H) from seat contact to tip of stem.

Discard valve if length is not

within limits specified in the following table.

Location

Sizes and Fits of New Parts inches (mm)

Wear Limits

A

(Intake valve seat angle)

15° ± 15'

B

(Intake valve seat width)

0.0890 (2.260)

0.0990 (2.514)

0.1200 (3.048)

C

(back grind angle)

30°

D

(Exhaust valve seat angle)

45° +15'/-0'

E

(Exhaust valve seat width)

0.0600 (1.524)

0.0700 (1.778)

0.1200 (3.048)

F

Regrind on this line when width of seat exceeds 0.120-inch (3.048mm)

G

(intake valve length)

6.355 (161.417)

6.369 (161.773)

6.3740 (161.900)

H

(exhaust valve length)

7.010 (178.054)

7.024 (178.410)

7.0340 (178.664)

END OF WORK PACKAGE

INTAKE

VALVE

EXHAUST

VALVE

A

B

B

A

C

D

E

E

D

C

G

H

F

F

WP 0145 00-4