Chrysler Dodge Caravan 2002 Manual page 1234

RS
VALVE SPRINGS & SEALS (Continued)
REMOVAL - CYLINDER HEAD OFF
(1) With cylinder head removed from cylinder
block, compress valve springs using a universal valve
spring compressor.
(2) Remove valve retaining locks, valve spring
retainers, valve stem seals and valve springs.
(3) Before removing valves, remove any burrs
from valve stem lock grooves to prevent dam-
age to the valve guides. Identify valves, locks and
retainers to insure installation in original location.
(4) Inspect the valves. (Refer to 9 - ENGINE/CYL-
INDER HEAD/VALVE SPRINGS - INSPECTION)
INSPECTION
(1) Whenever valves have been removed for inspec-
tion, reconditioning or replacement, valve springs
should be tested for correct tension. Discard the
springs that do not meet specifications. The following
specifications apply to both intake and exhaust
valves springs:
• Valve Closed Nominal Tension—76 lbs. @ 38.0
mm (1.50 in.)
• Valve Open Nominal Tension—136 lbs. @ 29.75
mm (1.17 in.)
(2) Inspect each valve spring for squareness with a
steel square and surface plate, test springs from both
ends. If the spring is more than 1.5 mm (1/16 inch)
out of square, install a new spring.
INSTALLATION
INSTALLATION - CYLINDER HEAD ON
(1) Install valve seal/valve spring seat assembly
(Fig. 34). Push the assembly down to seat it onto the
valve guide.
(2) Install valve spring and retainer, use Special
Tool MD-998772-A with adapter 6779 to compress
valve springs only enough to install locks (Fig. 33).
Correct alignment of tool is necessary to avoid nick-
ing valve stems.
(3) Remove air hose and install spark plugs.
(4) Install camshafts (Refer to 9 - ENGINE/CYL-
INDER HEAD/CAMSHAFT(S) - INSTALLATION).
(5) Install cylinder head cover (Refer to 9 -
ENGINE/CYLINDER
COVER - INSTALLATION).
INSTALLATION - CYLINDER HEAD OFF
(1) Coat valve stems with clean engine oil and
insert in cylinder head.
(2) Install new valve stem seals on all valves
using a valve stem seal tool (Fig. 35). The valve stem
seals should be pushed firmly and squarely over
valve guide.
HEAD/CYLINDER
Fig. 34 Valve Stem Seal/Valve Spring Seat
1 - VALVE RETAINING LOCKS
2 - VALVE SPRING
3 - VALVE SEAL AND VALVE SPRING SEAT ASSEMBLY
4 - VALVE SPRING RETAINER
CAUTION: When oversize valves are used, the cor-
responding oversize valve seal must also be used.
Excessive guide wear may result if oversize seals
are not used with oversize valves.
Fig. 35 Valve Stem Oil Seal Tool
1 - VALVE SEAL TOOL
2 - VALVE STEM
(3) Install valve springs and retainers. Compress
HEAD
valve springs only enough to install locks, taking
care not to misalign the direction of compression.
Nicked valve stems may result from misalignment of
the valve spring compressor.
CAUTION: When depressing the valve spring retain-
ers with valve spring compressor the locks can
become dislocated. Ensure both locks are in the
correct location after removing tool.
ENGINE 2.4L 9 - 33