20-14 Chapter 2 Part D General engine overhaul procedures
8.2 A small plastic bag, with an appropriate label, can be used
8.3 Use a valve spring compressor to compress the spring, then
to store the valve train components so they can be kept together
remove the keepers from the valve stem
and reinstalled in the original location
2 Before the valves are removed, arrange to label and store them,
along with their related components, so they can be kept separate and re-
installed in their original locations
(see illustration).
3 Compress the springs on the first valve with a spring compressor and
remove the keepers
(see illustration).
Carefully release the valve spring
compressor and remove the retainer, the spring and the spring seat (if
used).
I
4 Pull the valve out of the head, then remove the oil seal from the guide.
If the valve binds in the guide (won’t pull through), push it back into the
headanddeburrtheareaaround the keepergroovewithafinefileorwhet-
stone
(see illustration).
5 Repeattheprocedurefortheremainingvalves. Remembertokeepall
the parts for each valve together so they can be reinstalled in the same
locations.
6 Once the valves and related components have been removed and
stored in an organized manner, the head should be thoroughly cleaned
and inspected. If a complete engine overhaul is being done, finish the en-
ginedisassembly procedures before beginning the cylinder head cleaning
and inspection process.
8.4 If the valve won’t pull through the guide, deburr the edge
of
the stem end and the area around the top of the keeper groove
with a file or whetstone
9 Cylinder head - cleaning and inspection
1 Thorough cleaning of the cylinder head(s) and related valve train
components, followed by a detailed inspection, will enable you to decide
how much valve service work must be done during the engine overhaul.
Note:
lftheengine wasseveretyoverheafed, fhecylinderheadisprobably
warped.
Cleaning
2 Scrape all traces of old gasket material and sealant off the head gas-
ket, intake manifold and exhaust manifold mating surfaces. Be very care-
ful not to gouge the cylinder head. Special gasket removal solvents that
soften gaskets and make removal much easier are available at auto parts
stores.
3 Remove all built-up scale from the coolant passages.
4 Run a stiff wire brush through the various holes to remove deposits
that may have formed in them.
5 Run an appropriate size tap into each of the threaded holes to remove
corrosion and thread sealant that may be present. If compressed air is
available, use it to clear the holes of debris produced by this operation.
Warning:
Wear eye protection when using compressed air!
6 Clean the camshaft bearing cap bolt threads with a wire brush.
7 Clean the cylinder head with solvent and dry it thoroughly. Com-
pressed air will speed the drying process and ensure that all holes and re-
cessedareasareclean.
Note:
Oecarbonizingchemicalsareavaitableand
mayprove very useful when cleaning cylinder heads and valve train com-
ponents. They’re verycausticandshouldbeused with caution. Besure’to
follow the instructions on the container.
8 Clean the rocker arms and bearing caps with solvent and dry them
thoroughly (don’t mix them upduring the cleaning process). Compressed
air will speed the drying process and can be used to clean out the oil pas-
sages.
9 Clean all the valve springs, spring seats, keepers and retainers with
solvent and dry them thoroughly. Do the components from one valve at s
time to avoid mixing up the parts.
10 Scrape off any heavy deposits that may have formed on the valves,
then use a motorized wire brush to remove deposits from the valve heads
and stems. Again, make sure the valves don’t get mixed up.
Inspection
Refer to illustrations 9.12, 9.14, 9.15, 9.16, 9.17, and 9.18
Note:
Be sure to perform at/ of the following inspection procedures before
concluding machine shop work is required. Make a list of fhe items that
need attention.
Cylinder head
11 Inspect the head very carefully for cracks, evidence of coolant leak-
age and other damage. If cracks are found, check with an automotive ma-
chine shop concerning repair. If repair isn’t possible, a new cylinder head
should be obtained.
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