TM 5-3810-300-24&P-3
Cylinder Head 1.2
Fig. 15-Cylinder Head Bolt Tightening Sequence
disturbing the gaskets and seals, install guide studs J
No. 2, or equivalent, to the threads and underside of the
9665 in two corner bolt holes in the cylinder block.
head of all cylinder head attaching bolts (to stud threads
and head contact surface of stud nuts, if used). Then
install a bolt through each piloting sleeve (four- valve
NOTE: Current four-valve cylinder heads have
head) at the corners of the head and thread them finger
piloting sleeves installed in the corner bolt holes
tight into the cylinder block. Continue to tighten these
on the camshaft side of the head (former heads
bolts (finger tight) as the head is lowered into position on
had the piloting sleeves on the exhaust side).
the cylinder block.
The sleeves provide more accurate alignment of
the cylinder head with the block bores. Do not
NOTE: Either one of two types of stud nuts are
install the guide studs in the bolt holes which
line- up with piloting sleeves in the head. The
used. Both faces of one nut are square with the
guide studs are not required on early engines
threads. The other type nut has a shoulder on
which include cylinder head studs in the block.
one face. The shoulder side must contact the
cylinder head.
3. Insert the hooks of a chain, attached to a hoist, in
the vent holes of the cylinder head, or the lifter brackets,
IMPORTANT: Cylinder head bolts are especially
and lift the head into position above thev cylinder block.
designed for this purpose and must not be
replaced by ordinary bolts.
4. Make a final visual check of the compression
gaskets and seals to ensure that they are in place before
7. After the head is in place, remove the guide studs
the cylinder head is lowered. This is a very important
and chain hoist and install the remaining bolts. However,
check. Gaskets and seals which are not seated properly
before tightening the bolts (or nuts), loosen - the lifter
will cause leaks and " blow-by" and result in poor engine
bracket-to-cylinder head attaching bolts, otherwise the
performance and damage to the engine.
head may be prevented from seating properly on the
cylinder block. A similar condition could exist if the
5. Wipe the bottom of the cylinder head clean. Then
exhaust manifold is attached to the cylinder head.
lower the head until it is about I/2 " from the surface of
Clearance must be assured between the exhaust
the cylinder block.
manifold and the bosses on the cylinder block. On some
engine models, these bosses serve as a rest
6.
Apply a small amount of International Compound
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