1988 OPEL CALIBRA wheel bolt torque

7If any of the ring end gaps exceed the
specified tolerance, the relevant rings will have
to be renewed, and if the ring grooves in the
pistons are worn, new pistons may be required.
8Clean out the piston ring grooves using a
piece of old piston ring as a scraper. Take
care not to scratch the surface of the pistons.
Protect your fingers, piston ring edges are
sharp. Also probe the groove oil return holes,
to ensure that they are not blocked.
9Check the cylinder bores for signs of wear
ridges towards the top of the bores. If wear
ridges are evident, and new piston rings are
being fitted, the top ring must be stepped to
clear the wear ridge, or the bore must be
de-ridged using a scraper.
10Fit the oil control ring sections with the
lower steel ring gap offset 25 to 50 mm to the
right of the spreader ring gap, and the upper
steel ring gap offset by the same distance to
the left of the spreader ring gap.
11Fit the lower compression ring, noting that
the ring is tapered or stepped. The ring should
be fitted with the word “TOP” uppermost.
12Fit the upper compression ring, and offset
the ring gap by 180°to the lower compression
ring gap. If a stepped ring is being fitted, fit
the ring with the smaller diameter of the step
uppermost.
13If new pistons are to be fitted, they must
be selected from the grades available, after
measuring the cylinder bores as described in
Section 36.
14Normally the appropriate oversize pistons
are supplied by the dealer when the block is
rebored.15Whenever new piston rings are being
installed, the glaze on the original cylinder
bores should be “broken”, using either
abrasive paper or a glaze-removing tool in an
electric drill. If abrasive paper is used, use
strokes at 60°to the bore centre line, to create
a cross-hatching effect.
34Crankshaft and bearings -
removal and refitting
4
Note: New main bearing cap bolts must be
used on refitting
Removal
1With the engine removed from the vehicle,
continue as follows.
2Remove the cylinder head, as described
previously in Section 20.
3Remove the sump, oil pick-up pipe and
sump baffle (where applicable), as described
in Section 29.
4Remove the oil pump, as described in
Section 30.
5Remove the flywheel or flexplate (if
applicable), as described in Sections 25 and
26.
6Remove the pistons and connecting rods,
as described in Section 32.
7Invert the engine so that it is standing on
the top face of the cylinder block.
8The main bearing caps are numbered 1 to 4
from the timing belt end of the engine. The
rear (flywheel end) cap is not marked. Toensure that the caps are refitted the correct
way round, note that the numbers are read
from the coolant pump side of the engine with
the engine inverted (see illustration).
9Unscrew and remove the main bearing cap
bolts, and tap off the bearing caps. If the
bearing shells are to be re-used, tape them to
their respective caps.
10Note that the centre bearing shell
incorporates thrust flanges to control
crankshaft endfloat.
11Lift the crankshaft (complete with timing
sensor wheel, if fitted), from the crankcase.
12Extract the upper bearing shells, and
identify them for position if they are to be
re-used.
13The crankshaft, bearings and sensor
wheel can be examined for wear and damage,
as described in Section 35, and the cylinder
block and bores can be examined as
described in Section 36.
Refitting
14Begin refitting by ensuring that the
crankcase and crankshaft are thoroughly
clean, and that all oilways are clear. If
possible, blow through the oil drillings with
compressed air, and inject clean engine oil
into them.
15If the crankshaft is being replaced, where
applicable, transfer the timing sensor wheel
and tighten to correct torque.
16Wipe clean the bearing shell seats in the
crankcase and the bearing caps, then fit the
upper bearing shells to their seats.
17Note that there is a tag on the back of
each bearing shell, which engages with a
groove in the relevant seat in the crankcase or
bearing cap (see illustration).
18If new bearing shells are being fitted, wipe
away all traces of protective grease.
SOHC engine procedures 2A•31
33.6 Measuring a piston ring end gap
using a feeler blade34.8 Main bearing cap identification mark
(arrowed) - 1.6 litre engine34.17 Main bearing shell tag (arrowed)
engages with groove in cylinder block -
2.0 litre SOHC engine
33.5C Sectional view showing correct
orientation of piston rings - all engines33.5B Removing the centre section of the
oil control ring - 2.0 litre SOHC engine
2A
A good alternative to
compressed air, is to use a
water dispersing lubricant
spray into each hole, using
the spout provided.

31Refit the previously removed
components, referring to the relevant
Sections of this Chapter.
35Crankshaft and bearings -
examination
4
Examination
1Examine the crankpin and main journal
surfaces for signs of scoring or scratches, and
check the ovality and taper of the crankpins
and main journals. If the bearing surface
dimensions do not fall within the tolerance
ranges given in the Specifications at the
beginning of this Chapter, the crankpins
and/or main journals will have to be reground.
2Big-end and crankpin wear is accompanied
by distinct metallic knocking, particularly
noticeable when the engine is pulling from low
revs, and some loss of oil pressure.
3Main bearing and main journal wear is
accompanied by severe engine vibration rumble
- getting progressively worse as engine rev’s
increase - and again by loss of oil pressure.
4If the crankshaft requires regrinding, take it
to an engine reconditioning specialist, who
will machine it for you and supply the correct
undersize bearing shells.
5Inspect the big-end and main bearing shells
for signs of general wear, scoring, pitting and
scratches. The bearings should be matt grey
in colour. With leadindium bearings, should a
trace of copper colour be noticed, the
bearings are badly worn, as the lead bearing
material has worn away to expose the indium
underlay. Renew the bearings if they are in
this condition, or if there are any signs of
scoring or pitting. You are strongly advised
to renew the bearings - regardless of their
condition at time of major overhaul.
Refitting used bearings is a false economy.
6The undersizes available are designed to
correspond with crankshaft regrind sizes. Thebearings are in fact, slightly more than the
stated undersize, as running clearances have
been allowed for during their manufacture.
7Main and big-end bearing shells can be
identified as to size by the marking on the
back of the shell. Standard size shell bearings
are marked STD or .00, undersize shells are
marked with the undersize such as 0.020 u/s.
This marking method applies only to
replacement bearing shells, and not to those
used during production.
8An accurate method of determining bearing
wear is by using a Plastigage. The crankshaft
is located in the main bearings (and, if
necessary, the big-end bearings), and the
Plastigage filament is located across the
journal. Vauxhall recommend that the
crankshaft journal and bearing shells are
lightly lubricated, to prevent the Plastigage
from tearing as the bearing cap is removed.
The bearing cap should be fitted, and the
bolts tightened to the specified torque. The
cap is then removed, and the width of the
filament is checked against a scale that shows
the bearing running clearance. The clearance
should be compared with that given in the
Specifications.
9Where applicable, check the teeth of the
crankshaft TDC sensor wheel for damage
(see illustration). If evident, the crankshaft
must be renewed.
10Similarly, check the condition of the pins
in the front crankshaft balance weight, which
serve as detect points for the plug-in
diagnostic sensor used by Vauxhall dealers
(see illustration).
36Cylinder block and bores -
examination and renovation
4
Examination
1Examine the cylinder bores for taper,
ovality, scoring and scratches. Start bycarefully examining the top of the cylinder
bores. If they are at all worn, a very slight
ridge will be found on the thrust side. This
marks the top of the piston ring travel. The
owner will have a good indication of the bore
wear before dismantling the engine, or
removing the cylinder head. Excessive oil
consumption, accompanied by blue smoke
from the exhaust, is a sure sign of worn
cylinder bores and piston rings.
2Measure the bore diameter across the
block, and just below any ridge. This can be
done with an internal micrometer or a dial
gauge. Compare this with the diameter of the
bottom of the bore, which is not subject to
wear. If no measuring instruments are
available, use a piston from which the rings
have been removed, and measure the gap
between it and the cylinder wall with a feeler
blade. Refer to the Specifications. If the
cylinder wear exceeds the permitted
tolerances, then the cylinders will need
reboring, in which case note the following
points:
a)Piston and cylinder bores are closely
matched in production. The actual
diameter of the piston is indicated by
numbers on its crown; the same numbers
stamped on the crankcase indicate the
bore diameter
b)After reboring has taken place, the
cylinder bores should be measured
accurately and oversize pistons selected
from the grades available to give the
specified piston-to-bore clearance
c)For grading purposes, the piston diameter
is measured across the bottom of the skirt
3If the wear is marginal and within the
tolerances given, new special piston rings can
be fitted to offset the wear.
4Thoroughly examine the crankcase and
cylinder block for cracks and damage, and
use a piece of wire to probe all oilways and
waterways to ensure that they are
unobstructed.
SOHC engine procedures 2A•33
35.10 Check the condition of the pins (arrowed) in the front
crankshaft balance weight - 2.0 litre SOHC engine35.9 Check the condition of the TDC sensor wheel teeth at the
front of the crankshaft - 2.0 litre SOHC engine
2A