Page 65 - Mechanic Diesel - TT
P. 65
MECHANIC DIESEL - CITS
You already know that valves are located in the cylinder block of the L-head engine, in the cylinder head of the
I-head engine, and in both the block and the head of the F-head engine.
Valve Installation from constant use, valves shape themselves to the valve seat. When reusing old valves, be
certain that you install each valve in its original location to ensure proper seating. This holds true for all valves,
whether you are installing them in the head or in the block. Insert the valve stem first into the valve guide from the
bottom of the head. If the valves are equipped with seals, place the valve spring and valve spring retainer over
the valve stem and compress the valve spring into place with the valve spring compressing tool.
After compressing the valve spring, insert the valve stem locks However, in some cases you may find that a
sleeve is used. This is placed on the valve stem before the locks. If a valve stem cap is used, it is placed over
the end of the valve stem after the locks are in place and the valve spring released. Figure 6-14 is an example of
valves and their associated components. You might note that the valve stem locks are sometimes referred to as
keys. When all valves are installed in the cylinder head, the head is ready to be installed on the cylinder block.
Cylinder Head and Pushrod Installation
Now you are ready to install the cylinder head. Since the L-head engine is the simplest of heads to install, let’s
discuss it first. Inspect your cylinder head gasket. In many cases, you will find one side marked “TOP.” Be sure
to place the gasket on the cylinder block so that the word “TOP” may be seen. In cases where the gasket is not
marked, inspect the alignment of the holes in the block with the holes in the gasket. If the holes are not aligned,
you have the gasket inverted, or bottom side up.
Now, place the cylinder head in position over the gasket and insert the cylinder head bolts. Screw the bolts into
the cylinder block until they are snug against the cylinder head. You must use a torque wrench to tighten the
cylinder head bolts.
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CITS : Automotive - Mechanic Diesel - Lesson 11 - 14