Dodge 2000 DURANGO Service Manual page 605

9 - 96 5.2L ENGINE
SERVICE PROCEDURES (Continued)
(2) Attach Dial Indicator Tool C-3339 to cylinder
head and set it at right angle of valve stem being
measured (Fig. 18).
Fig. 18 Measuring Valve Guide Wear
1 – VALVE
2 – SPECIAL TOOL C-3339
(3) Move valve to and from the indicator. The total
dial indicator reading should not exceed 0.432 mm
(0.017 inch). Ream the guides for valves with over-
size stems if dial indicator reading is excessive or if
the stems are scuffed or scored.
Service valves with oversize stems are available as
shown below.
REAMER SIZES
REAMER O/S
0.076 mm (0.003 in.)
0.381 mm (0.015 in.)
Slowly turn reamer by hand and clean guide thor-
oughly before installing new valve. Ream the valve
guides from standard to 0.381 mm (0.015 inch).
Use a 2 step procedure so the valve guides are
reamed true in relation to the valve seat:
• Step 1—Ream to 0.0763 mm (0.003 inch).
• Step 2—Ream to 0.381 mm (0.015 inch).
REFACING VALVES AND VALVE SEATS
The intake and exhaust valves have a 43-1/4° to
43-3/4° face angle and a 44-1/4° to 44-3/4° seat angle
(Fig. 19).
VALVES
VALVE GUIDE SIZE
8.026 - 8.052 mm
(0.316 - 0.317 in.)
8.331 - 8.357 mm
(0.328 - 0.329 in.)
Fig. 19 Valve Face and Seat Angles
1 – CONTACT POINT
VALVE FACE AND VALVE SEAT ANGLE CHART
ITEM DESCRIPTION
A SEAT WIDTH–
INTAKE
SEAT WIDTH–
EXHAUST
B FACE ANGLE
(INT. and EXT.)
C SEAT ANGLE
(INT. and EXT.)
D CONTACT
SURFACE
Inspect the remaining margin after the valves are
refaced (Fig. 20). Valves with less than 1.190 mm
(0.047 inch) margin should be discarded.
VALVE SEATS
CAUTION: DO NOT un-shroud valves during valve
seat refacing (Fig. 21).
(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-
ing stones. A true and complete surface must be
obtained.
(2) Measure the concentricity of valve seat using a
dial indicator. Total runout should not exceed 0.051
mm (0.002 inch) total indicator reading.
DN
SPECIFICATION
1.016 - 1.524 mm
(0.040 - 0.060 in.)
1.524 - 2.032 mm
(0.060 - 0.080 in.)
43 1 ⁄ ° - 43 3 ⁄ °
4 4
44 1 ⁄ ° - 44 3 ⁄ °
4 4
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