TM 5-3895-346-14
CYLINDER HEAD
ENGINE OVERHAUL
6.
Check the water hole nozzles (four-valve head only) to be sure they are not loose. If necessary,
replace the nozzles as follows:
a.
Remove the old nozzles.
b.
Make sure the water inlet ports in the cylinder head are clean and free of scale. The water
holes may be cleaned up with a 5/8-inch drill. Break the edges of the holes slightly.
c.
Press the nozzles in place with the nozzle openings positioned as shown in Fig. 5. Press the
nozzles flush to 0.0312-inch recessed below the surface of the cylinder head.
d.
Check to make sure the nozzles fit tight. If
necessary, use a wood plug or other suitable tool to expand the
nozzles, or tin the outside diameter with solder to provide a tight fit.
If solder is used, make sure the orifices in the nozzles are not
closed with solder. Figure 5. Correct Installation of Water Nozzles
in Four-Valve Cylinder Head
7.
Replace broken or damaged exhaust manifold studs.
Apply sealant to the threads and drive new studs to 25-40 lb ft (34-
54 Nm) torque (1.40-1.50-inches height).
8.
Inspect all other components removed from the cylinder
head.
If a service replacement cylinder head is to be installed, it must be
Figure 5. Correct Installation of Water
thoroughly cleaned of all rust preventive compound, particularly
Nozzles in Four-Valve Cylinder Head
inside the integral fuel manifolds, before installing the plugs. A
simple method of removing the rust-preventive compound is to immerse the head in mineral spirits-based
solvent or fuel oil, then scrub the head and go through all the openings with a soft bristle brush. A suitable
brush for cleaning the various passages in the head can be made by attaching a 1/8-inch diameter brass rod to
brush J 8152. After cleaning, dry the cylinder head with compressed air.
A service replacement cylinder head includes the exhaust valve guides, valve seat inserts, water nozzles,
injector tubes, and the necessary plugs.
Assemble Cylinder Head
After cleaning and inspection, assemble the cylinder head as follows:
1.
Coat the threads of the plugs with Loctite Pipe Sealant with Teflon, then install the necessary plugs
and tighten them to the specified torque (Specifications). Drive headless plugs flush to 0.0625 inch below the
surface of the cylinder head.
2.
After the following parts are cleaned and inspected, and replaced if necessary, reinstall them in the
old cylinder head or transfer them to the new head.
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