Figure 3-36. Valve and injector counterbore dimensions.

TM 9-2815-213-34

(2) Measure head height using micrometer or

in same direction as cutter; tighten assembly in place.

vernier calipers; dimensions must not exceed

(4) Rotate cylinder head and install regrooving

4.4890/4.4990 inches.

cutter in injector bore (fig. 347).

(3) Restore counterbore and pocket depth at

(5) Check position of stop in tool holder to make

valves and shallow counterbore area around injector port

certain it will not contact water hole during regrooving

(fig. 3-36) by grinding with a stone dressed to the

operation.

indicated contours.

(6) Adjust regrooving cutter so it protrudes

b. Regroove Cylinder Head. If cylinder head has

0.006/0.008 inch below stop. Rotate tool clockwise to cut

grooves. Do not rotate counterclockwise.

been resurfaced, regroove with grooving tool (33, fig. B-

28), as shown in figure 3-37.

(1) Select scrapped injector, preferably one with

CAUTION

class "0" plunger bore and injector cup. Cut off cup to

Do not attempt to cut deeper than cutter

expose plunger bore, to keep cup seal area intact.

groove depth or grooves will not form in

(2) Install injector in cylinder head and tighten

head. Groove lands should be

30/35 foot-pounds torque.

0.010/0.015 inch wide and must not

(3) Select correct tool spacer block, 0.940 inch

extended above head surface

thick. Assemble the regrooving tool, positioning largest

pilot pin so it protrudes downward

Figure 3-36. Valve and injector counterbore dimensions.

Grind Valves.

(1) Wet grind valve from horizontal to exactly 30

degree angle.

(2) Inspect rim thickness after grinding as shown

in figure 332; if rim is less than 1/16 inch, valve is not

suitable for use and must be replaced.

(3) Check valve in reamed guide and against

newly ground valve seat face. Pencil mark valve face and

drop into position and rotate 10 degrees. A good seat will

be indicated if all pencil marks are broken. If pencil

marks are not broken either valve seat or valve refacing

tools have not been properly adjusted; final check should

be made with vacuum tester.

3-68. Assembly

a. Valve Guide.

Figure 3-37. Cylinder head regrooving.

3-19