Valve Lifters-Removal, Inspection And Installation - Jeep cherokee 1989 Owner's Manual

14.12 Lubricating the thrust surface of the camshaft sprocket
1 2 Lubricate the thrust (rear) surface of the camshaft sprocket with
moly-base grease or engine assembly lube (see illustration). Install the
timing chain over the camshaft sprocket with slack in the chain hang-
ing down over the crankshaft sprocket.
13 With the timing marks aligned, slip the chain over the crankshaft
sprocket and then draw the camshaft sprocket into place with the three
retaining bolts. Do not hammer or attempt t o drive the camshaft
sprocket into place, as it could dislodge the welch plug at the rear of
the engine.
14 With the chain and both sprockets in place, check again to ensure
that the timing marks on the t w o sprockets are properly aligned. If not,
remove the camshaft sprocket and move
15 Lubricate the chain with engine oil and install the remaining com-
ponents in the reverse order of removal.
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1 5 Valve lifters removal, inspection and installation
Refer to illustrations 15.7a and 15. 76
1 A noisy valve lifter can be isolated when the engine is idling. Hold
a mechanic's stethoscope or a length of hose near the position of each
valve while listening at the other end. Another method is to remove
the rocker arm cover and, with the engine idling, place a finger on each
of the valve spring retainers, one at a time. If a valve lifter is defective,
it will be evident from the shock felt at the retainer as the valve seats.
2 The most likely causes of noisy valve lifters are dirt trapped be-
tween the plunger and the lifter body or lack of oil flow, viscosity or
pressure. Before condemning the lifters, we recommend checking the
oil for fuel contamination, correct level, cleanliness and correct viscosity.
Removal
3 Remove the rocker arm cover(s) as described in Section 4.
4
Remove the intake manifold as described in Section 8.
5 Remove the rocker arms and pushrods (Section 5).
6
There are several ways to extract the lifters from the bores. A
special tool designed to grip and remove lifters is manufactured by many
tool companies and is widely available, but it may not be required in
every case. On newer engines without a lot of varnish buildup, the
lifters can often be removed with a small magnet or even with your
fingers. A machinist's scribe with a bent end can be used t o pull the
lifters out by positioning the point under the retainer ring in the top
of each lifter. Caution: Don't use pliers to remove the lifters unless
you intend to replace them with new ones (along with the camshaft).
The pliers may damage the precision machined and hardened lifters,
rendering them useless.
7
Before removing the lifters, arrange t o store them in a clearly la-
belled box to ensure that they're reinstalled in their original locations.
Note: Some engines may have both standard and 0.25 mm (0.0 10-
inch) oversize valve lifters installed at the factory. These are specially
The Motor Manual Guy
Chapter 2 Part B
it until the marks align.
marked (see illustration). Remove the lifters and store them where they
won't get dirty (see illustration).
Inspection and installa tion
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quired to remove them from the engine again if cleaning is unsuccessful
outweighs any potential savings from repairing them. Refer to Chap-
ter 2, Part A, for lifter and camshaft inspection procedures. If the lifters
are worn, they must be replaced with new ones and the camshaft must
be replaced as well
or new lifters with a used camshaft.
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original bores. Soak new lifters in oil to remove trapped air. Coat all
lifters with moly-base grease or engine assembly lube prior t o instal-
lation.
1 0 The remaining installation steps are the reverse of removal.
11 Run the engine and check for oil leaks.
1 6 Camshaft and bearings
Refer to illustrations 16. 10, 16. 1 1 and 16. 13
Note: Before removing the camshaft, refer to Chapter 2, Part A /See-
1
2
3
4
5
V6 engine
lifters, the lifter boss will be marked with a dab of white
paint and will have 0.25 (mm) OS stamped on i t
As the lifters are removed from the engine block,
they should be stored separately to ensure reinstallation in
their original positions
Parts for valve lifters are not available separately. The work re-
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never install used lifters with a new camshaft
When reinstalling used lifters, make sure they're replaced in their
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removal, inspection and installation
Remove the cable from the negative battery terminal.
Drain the oil from the crankcase (refer to Chapter 1
Drain the coolant from the radiator (refer to Chapter 1
Remove the radiator (refer to Chapter 3).
If equipped with air conditioning, remove the condenser (refer to
2B-9