Valve Rocker Arm And/Or Shaft Assembly; Push Rods; Cylinder Block; Repairing Sand Holes Or Porous Engine Castings - Ford VSG-411 Service Manual

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Basic Engine
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FllTlNG PISTON PINS
The piston pins are selected to give the correct fit in the piston
pin bore and bushing in the connecting rod. Pistons are only
supplied in service complete with the piston pin, to ensure the
correct fit. The piston pins should not be interchanged.
VALVE ROCKER ARM AND/OR SHAFT
ASSEMBLY
Dress up minor surface defects on the rocker arm shaft and in the
rocker arm bore with a hone.
If the pad at the valve end of the rocker arm has a grooved
radius, replace the rocker arm. Do not attempt to true this
surface by grinding.
PUSH RODS
Following the procedures under Push Rod Inspection, check the
push rods for straightness.
If the runout exceeds the maximum limit at any point, discard
the rod. Do not attempt to straighten push rods.
CYLINDER BLOCK
REFINISHING CYLINDER WALLS
Honing is recommended for refinishing cylinder walls only
when the walls have minor scuffs or scratches, or for fitting pistons
to the specified clearance. The grade of hone to be used is deter-
mined by the amount of metal to be removed. Follow the instruc-
tions of the hone manufacturer. If coarse stones are used to start the
honing operation, leave enough material so that all hone marks can
be removed with the finishing hone which is used to obtain the
proper piston clearance. Cylinder walls that are severely marred
and/or worn beyond the specified limits should be refinished.
Before any cylinder is refinished, all main bearing caps must
be in place and tightened to the proper torque so that the
crankshaft bearing bores will not become distorted from the
refinishing operation. Refinish only the cylinder or cylinders that
require it. All pistons are the same weight, both standard and
oversize; therefore, various sizes of pistons can be used without
upsetting engine balance. Refinish the cylinder with the most wear
first to determine the maximum oversize. If the cylinder will not
clean up when refinished for the maximum oversize pistonrecom-
mended, replace the block. Refinish the cylinder to within approx-
imately 0.0015 inch of the required oversize diameter. This will
allow enough stock for the final step of honing so that the correct
surface finish and pattern are obtained. For the proper use of the
refinishing equipment follow the instructions of the manufacturer.
Only experienced personnel should be allowed to perform this
work. Use a motor-driven, spring pressure-type hone at a speed of
300500 rpm. Hones of grit sizes 180-220 will normally provide
the desired bore surface finish of 15/32 RMS. When honing the
cylinder bores use a lubricant mixture of equal parts of kerosene
and SAE No. 20 motor oil. Operate the hone in such a way to
produce a cross-hatch finish on the cylinder bore. The cross-hatch
pattern should be at an angle of approximately 30 degrees to the
cylinder bore. After the final operation in either of the two re-
finishing methods described and prior to checking the piston fit,
thoroughly clean and oil the cylinder walls. Mark the pistons to
correspond to the cylinders in which they are to be installed. When
the refinishing of all cylinders that require it has been completed
and all pistons are fitted, thoroughly clean the entire block and oil
the cylinder walls.
REPAIRING SAND HOLES OR
POROUS ENGINE CASTINGS
Porosity or sand hole(s) which will cause oil seepage or leakage
can occur with modem casting processes. A complete inspection
of engine and transmission should be made. If the leak is attributed
to the porous condition of the cylinder block or sand hole(s),
repairs can be made with metallic plastic (part No. C6AZ- 19554-
A). Do not repair cracks with this material. Repairs with this
metallic plastic must be confined to those cast iron engine compo-
nent surfaces where the inner wall surface is not exposed to engine
coolant pressure or oil pressure. For example:
1. Cylinder block surfaces extending along the length of the
block, upward from the oil pan rail to the cylinder water jacket
but not including machined areas.
2. Lower rear face of the cylinder block.
3. Intake manifold casting.
4. Cylinder head, along the rocker arm cover gasket surface.
The following procedure should be used to repair porous areas
or sand holes in cast iron.
a. Clean the surface to be repaired by grinding or rotary filing
to a clean bright metal surface. Chamfer or undercut the
hole or porosity to a greater depth than the rest of the
cleaned surface. Solid metal must surround the hole.
Openings larger than l/4 inch should not be repaired using
metallic plastic. Openings in excess of l/4 inch can be
drilled, tapped and plugged using common tools. Clean
the repair area thoroughly. Metallic plastic will not stick to
a dirty or oily surface.
b. Mix the metallic plastic base and hardener as directed on
the container. Stir thoroughly until uniform.
c. Apply the repair mixture with a suitable clean tool, (putty
knife, wood spoon, etc.) forcing the epoxy into the hole or
porosity.
d. Allow the repair mixture to harden. This can be accom-
plished by two methods, heat cure with a 250 degree lamp
placed 10 inches from the repaired surface, or air dry for
lo- 12 hours at temperatures above 50 degrees F.
e. Sand or grind the repaired area to blend with the general
contour of the surrounding surface.
f. Paint the surface to match the rest of the block.