Figure 6-13. Installing New Rocker Arm Studs.

TM 10-3930-633-34

TS007343

Figure 6-14. Reaming Valve Guides.

(1) When reaming guides for oversize valves,

use the smallest reamer first, then the finish size

reamer.

(2) Use a suitable scraper or deburring tool

to break the sharp edge at the top of the valve

(3) Always reface seat after reaming valve

guides.

c. Refacing Value Seats. Refacing of the valve

seat should be closely coordinated with the

refacing of the valve face so that the finished seat

Figure 6-13. Installing New Rocker Arm Studs.

and valve face will be concentric and the specified

interference fit will be maintained. This is im-

(5) Align the stud and installer with the stud

portant so that the valve and seat will have a

bore, then tap the sliding driver until it bottoms.

compression tight fit. Be sure that the refacer

When the installer contacts the stud boss, the

grinding wheels are properly dressed.

stud is installed to its correct height.

b. Reaming V a l v e Guides. If it becomes

(1) Grind the valve seats to a true 45 degree

angle (figure 6-15 ). Remove only enough stock to

necessary to ream a valve guide (fig. 6-14) to

clean up pits and grooves or to correct the valve

install a valve with an oversize stem, a reaming

seat runout. After the seat has been refaced, use a

kit is available which contains the following

seat width scale or a machinist scale to measure

reamer and pilot combinations: an 0.003 inch OS

the seat width. Narrow the seat, if necessary, to

reamer with a standard diameter pilot, an 0.015

bring it within specifications.

inch OS reamer with an 0.003 inch OS pilot, and

an 0.030 inch reamer with an 0.015 inch OS pilot.