Cylinder Heads Cleaning And Inspection - Ford LSG 875 Service Manual

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BASIC ENGINE
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CLEANING AND INSPECTION (Continued)
CYLINDER HEADS
Cleaning
With the valves installed to protect the
valve seats, remove deposits from the com-
bustion chambers and valve heads with a
scraper and a wire brush. Be careful not to
damage the cylinder head gasket surface.
After the valves are removed, clean the valve
guide bores with a valve guide cleaning tool.
Use cleaning solvent to remove dirt, grease and
other deposits. Clean all bolt holes. Remove all
deposits from the valves with a fine wire brush
or buffing wheel.
Inspection
Check the cylinder head forcracks and in-
spect the gasket surface for burrs and nicks.
Replace the head if it is cracked.
The following inspection procedures are for a
cylinder head that is to be completely over-
hauled. For individual repair operations, use only
the pertinent inspection procedure.
When a cylinder head is removed because of
gasket leaks, check the flatness of the cylinder
head gasket surface for conformance to specifi-
cations. If necessary to refinish the cylinder
head gasket surface, do not plane or grind off
more than 0.254mm (0.010 inch).
@ @ CHECK DIAGONALLY
@ CHECK ACROSS CENTER
Check the valve seat runout with an accurate
gauge. Follow the instructions of the gauge
manufacturer. If the runout exceeds the wear
limit, reface the valve and valve seat. Measure
the valve seat width. Reface any valve seat
whose width is not within specifications.
Inspect the valve face and the edge of the
valve head for pits, grooves, scores or other
VALVE SEAT
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RUNOUT GAUGE
081 P-6002-E \
A9624-1 A
damage. Inspect the stem for a bent condition
and the end of the valve head for pits, grooves,
scores or other wear. Inspect the stem for a bent
condition and the end of the stem for grooves or
scores. Check the valve head for signs of burn-
ing, erosion, warpage and cracking. Minor pits,
grooves, etc., may be removed. Discard valves
that are severely damaged. Do not discard so-
dium-cooled valves with other scrap metal in
scrap bins. If a sodium-cooled valve is acci-
dentally broken and the sodium exposed, it
will react violently upon contact with water
resulting in fire and explosion due to chem-
ical action. Therefore, these valves should be
handled with care and disposed of by being
buried in the ground in an area not subjected
to excavation.
Inspect the valve spring, valve spring re-
tainers, locks and sleeves for wear or damage.
Discard any visually damaged parts.
Check the valve stem to valve guide clear-
ance of each valve in its respective valve guide
with the tool shown or its equivalent. Use a flat
end indicator point.