Dodge 2000 DURANGO Service Manual page 665

DN
SERVICE PROCEDURES (Continued)
Fig. 22 Refacing Valve Seats
1 – STONE
2 – PILOT
3 – VALVE SEAT
4 – SHROUD
inch). The width of the exhaust seats should be
1.524-2.032 mm (0.060-0.080 inch).
VALVE SPRING INSPECTION
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested. As an example the compression length of
the spring to be tested is 1-5/16 inch. Turn table of
Universal Valve Spring Tester Tool until surface is in
line with the 1-5/16 inch mark on the threaded stud.
Be sure the zero mark is to the front (Fig. 23). Place
spring over stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until
ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by 2. This will give the
spring load at test length. Fractional measurements
are indicated on the table for finer adjustments.
Refer to specifications to obtain specified height and
allowable tensions. Discard the springs that do not
meet specifications.
MEASURING TIMING CHAIN STRETCH
NOTE: To access timing chain Refer to Timing
Chain Cover in Removal and Installation Section.
(1) Place a scale next to the timing chain so that
any movement of the chain may be measured.
(2) Place a torque wrench and socket over cam-
shaft sprocket attaching bolt. Apply torque in the
direction of crankshaft rotation to take up slack; 41
N·m (30 ft. lbs.) torque with cylinder head installed
or 20 N·m (15 ft. lbs.) torque with cylinder head
removed. With a torque applied to the camshaft
Fig. 23 Testing Valve Spring for Compressed
1 – TORQUE WRENCH
2 – VALVE SPRING TESTER
sprocket bolt, crankshaft should not be permitted to
move. It may be necessary to block the crankshaft to
prevent rotation.
(3) Hold a scale with dimensional reading even
with the edge of a chain link. With cylinder heads
installed, apply 14 N·m (30 ft. lbs.) torque in the
reverse direction. With the cylinder heads removed,
apply 20 N·m (15 ft. lbs.) torque in the reverse direc-
tion. Note the amount of chain movement (Fig. 24).
Fig. 24 Measuring Timing Chain Wear and Stretch
1 – TORQUE WRENCH
2 – 3.175 MM
(0.125 IN.)
(4) Install a new timing chain, if its movement
exceeds 3.175 mm (1/8 inch).
(5) If chain is not satisfactory, remove camshaft
sprocket attaching bolt and remove timing chain with
crankshaft and camshaft sprockets.
(6) Place both camshaft sprocket and crankshaft
sprocket on the bench with timing marks on exact
imaginary center line through both camshaft and
crankshaft bores.
5.9L ENGINE
Length
9 - 155