and evenly the pressure of the valve springs
on the caps.
5 Withdraw the caps, noting their markings
and the presence of the locating dowels, then
remove the camshafts and withdraw their oil
seals. The inlet camshaft can be identified by
the reference lobe for the camshaft position
sensor; therefore, there is no need to mark the
camshafts (see illustrations).
6 Obtain sixteen small, clean containers, and
number them 1 to 16. Using a rubber sucker,
withdraw each hydraulic tappet in turn, invert
it to prevent oil loss, and place it in its
respective container, which should then be
filled with clean engine oil (see illustrations).
Do not interchange the hydraulic tappets, or
the rate of wear will be much increased. Do
not allow them to lose oil, or they will take a
long time to refill on restarting the engine,
resulting in incorrect valve clearances.
Inspection
7 With the camshafts and hydraulic tappets
removed, check each for signs of obvious
wear (scoring, pitting etc) and for ovality, and
renew if necessary.
8 Measure the outside diameter of each
tappet (see illustration) - take measurements
at the top and bottom of each tappet, then a
second set at right-angles to the first; if any
measurement is significantly different from the
others, the tappet is tapered or oval and must
be renewed. If the necessary equipment is
available, measure the inside diameter of the
corresponding cylinder head bore. Compare
the measurements obtained to those given
in the Specifications Section of this Chapter; if
the tappets or the cylinder head bores are
excessively worn, new tappets and/or a new
cylinder head will be required.
9 If the engine’s valve components have
sounded noisy, particularly if the noise
persists after initial start-up from cold, there is
reason to suspect a faulty hydraulic tappet.
Only a good mechanic experienced in these
engines can tell whether the noise level is
typical, or if renewal of one or more of the
tappets is warranted. If faulty tappets are
diagnosed, and the engine’s service history is
unknown, it is always worth trying the effect of
renewing the engine oil and filter (see Chap-
ter 1), using only good-quality engine oil of the
recommended viscosity and specification,
before going to the expense of renewing any
of the tappets - refer also to the advice in
Section 5 of this Chapter.
10 Visually examine the camshaft lobes for
score marks, pitting, galling (wear due to
rubbing) and evidence of overheating (blue,
discoloured areas). Look for flaking away of
the hardened surface layer of each lobe. If any
such signs are evident, renew the component
concerned.
11 Examine the camshaft bearing journals
and the cylinder head bearing surfaces for
signs of obvious wear or pitting. If any such
signs are evident, renew the component
concerned.
12 Using a micrometer, measure the
diameter of each journal at several points. If
the diameter of any one journal is less than
the specified value, renew the camshaft.
13 To check the bearing journal running
clearance, remove the hydraulic tappets, use
a suitable solvent and a clean lint-free rag to
clean carefully all bearing surfaces, then refit
the camshafts and bearing caps with a strand
of Plastigauge across each journal. Tighten
the bearing cap bolts to the specified torque
wrench setting (do not rotate the camshafts),
then remove the bearing caps and use the
scale provided to measure the width of the
compressed strands. Scrape off the
Plastigauge with your fingernail or the edge of
a credit card - don’t scratch or nick the
journals or bearing caps.
14 If the running clearance of any bearing is
found to be worn to beyond the specified
service limits, fit a new camshaft and
repeat the check; if the clearance is still
excessive, the cylinder head must be renewed.
15 To check camshaft endfloat, remove the
hydraulic tappets, clean the bearing surfaces
carefully, and refit the camshafts and bearing
Zetec engine in-car repair procedures 2C•9
11.6a Removing hydraulic tappets
11.5b Inlet camshaft has lobe for camshaft position sensor
11.5a Note locating dowels when removing camshaft bearing
caps
11.8 Use a micrometer to measure
diameter of hydraulic tappets
11.6b Hydraulic tappets must be stored as
described in text
2C
1595Ford Fiesta Remake