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2A•14 SOHC engines
29.4a Checking a piston ring gap at the top
of the cylinder
(1.0 in) either side of the spreader gap. Fit the
tapered lower compression ring with the TOP
mark towards the top of the piston and the gap
150° from the spreader gap, then fit the upper
compression ring with the gap 150° on the
other side of the spreader gap. Note that the
compression
rings
are
molybdenum skin which must not be damaged.
7 Note that the compression rings are made
of cast iron, and will snap if expanded too far.
30 Camshaft and cam followers
- examination and renovation
Examine the surface of the camshaft
journals and lobes and the cam followers for
wear. If excessive, considerable noise would
have been noticed from the top of the engine
and a new camshaft and followers must be
fitted.
Check the camshaft bearings for wear and if
necessary have them renewed by a Ford
garage.
Check the camshaft lubrication tube for
obstructions and make sure that the jet holes
are clear. Obstruction of the holes can be due
to sludge build-up which occurs when regular
oil changes have been neglected.
31 Auxiliary shaft - examination
and renovation
Examine the auxiliary shaft for wear and
damage and renew it if necessary.
If the auxiliary shaft endfloat is outside the
limits given in the Specifications fit a new
thrust plate. If this does not bring the endfloat
within limits, renew the shaft.
32 Timing belt - examination and
renovation
Whenever the timing belt is removed it is
worthwhile renewing it, especially if it has
covered a high mileage. This is more important
on the 2.0 litre engine where stripped teeth on
the timing belt can cause the pistons to foul
the valves.
29.4b Checking a ring gap at the bottom of
33 Flywheel ring gear -
examination and renovation
If the ring gear is badly worn or has missing
teeth, it should be renewed. The old ring can
coated
with
a
be removed from the flywheel by cutting a
notch between two teeth with a hacksaw and
then splitting it with a cold chisel. Wear eye
protection when doing this.
To fit a new ring gear requires heating the
ring to 204°C (400°F). This can be done by
polishing four equal sections of the gear,
laying it on a suitable heat resistant surface
(such as fire bricks) and heating it evenly with
a blow lamp or torch until the polished areas
turn a light yellow tinge. Do not overheat or the
hard wearing properties will be lost. The gear
has a chamfered inner edge which should go
against the shoulder when put on the flywheel.
When hot enough place the gear in position
quickly, tapping it home if necessary and let it
cool naturally, without quenching.
34 Cylinder head - decarbonising,
valve grinding and renovation
1 This operation will normally only be required
at comparatively high mileages. However, if
persistent pinking occurs and performance
has deteriorated even though the engine
adjustments are correct, decarbonising and
valve grinding may be required.
2 With the cylinder head removed, use a
scraper to remove the carbon from the
combustion chambers and ports. Remove all
traces of gasket from the cylinder head
surface, then wash it thoroughly with paraffin.
3 Use a straight-edge and feeler blade to
check that the cylinder head surface is not
distorted. If it is, it must be resurfaced by a
suitably equipped engineering works.
4 If the engine is still in the car, clean the
piston crowns and cylinder bore upper edges,
but make sure that no carbon drops between
the pistons and bores. To do this, locate two
of the pistons at the top of their bores and seal
off the remaining bores with paper and
masking tape. Press a little grease between
the two pistons and their bores to collect any
carbon dust; this can be wiped away when the
piston is lowered.
the cylinder
To prevent carbon build-up,
polish the piston crown with
metal polish, but remove all
traces of the polish after.
5 Examine the heads of the valves for pitting
and burning, especially the exhaust valve
heads. Renew any valve which is badly burnt.
Examine the valve seats at the same time. If
the pitting is very slight, it can be removed by
grinding the valve heads and seats together
with coarse, then fine, grinding paste.
6 Where excessive pitting has occurred, the
valve seats must be recut or renewed by a
suitably equipped engineering works.
7 Valve grinding is carried out as follows.
Place the cylinder head upside down on a
bench on blocks of wood.
8 Smear a trace of coarse carborundum paste
on the seat face and press a suction grinding
tool onto the valve head. With a semi-rotary
action, grind the valve head to its seat, lifting
the valve occasionally to redistribute the
grinding paste. When a dull matt even surface
is produced on both the valve seat and the
valve, wipe off the paste and repeat the
process with fine carborundum paste as
before. A light spring placed under the valve
head will greatly ease this operation. When a
smooth unbroken ring of light grey matt finish
is produced on both the valve and seat, the
grinding operation is complete.
9 Scrape away all carbon from the valve head
and stem, and clean away all traces of
grinding compound. Clean the valves and
seats with a paraffin soaked rag, then wipe
with a clean rag.
10 If the guides are worn they will need
reboring for oversize valves or for fitting guide
inserts. The valve seats will also need
recutting to ensure that they are concentric
with the stems. This work should be given to
your Ford dealer or local engineering works.
11 If the valve springs have been in use
for 20 000 miles (32 000 km) or more, renew
them. Always renew the valve stem oil seals
when the valves are removed.
35 Engine reassembly - general
information
1 To ensure maximum life with minimum
trouble from a rebuilt engine, not only must
everything be correctly assembled, but it must
also be spotlessly clean. All oilways must be
clear, and locking washers and spring washers
must be fitted where indicated. Oil all bearings
and other working surfaces thoroughly with
engine oil during assembly.
2 Before assembly begins, renew any bolts or
studs with damaged threads.
3 Gather together a torque wrench, oil can,
clean rag, and a set of engine gaskets and oil
seals, together with a new oil filter.
4 If they have been removed, new cylinder
head bolts and flywheel bolts will also be
required.
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