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 840 of 1563

TM 9-2815-220-24

ROCKER ARM ASSEMBLY AND COVER REPLACEMENT

0104 00

REMOVAL (Continued)

CAUTION

Do not remove the last four screws (primary fasteners) until valve

spring pressure has been relieved. Valve spring pressure must be

relieved at each cylinder as the rocker arm cover for that cylinder is

removed.

Failure to comply may damage cylinder threads that retain

rocker arm cover.

8. Release valve spring (22) tension.

a. Release the tension on valve rocker arms (23) and valve springs (22) by rotating engine

crankshaft until rocker arm rollers (24) are on camshaft base circle (valves are closed).

b. Check rocker arms (23) for free movement between adjusting screw pads (25) and valve

stems (26) on both exhaust and intake valves. If movement (clearance) cannot be felt,

rotate engine crankshaft until clearance is evident.

c. When clearance is obtained between adjusting screw pads (25) and valve stems (26),

rocker arm rollers (24) are on camshaft base circle, and valve spring tension is relieved.

24

26

25

23

22

WP 0104 00-8