Engine Components - Examination And Renovation; Crankshaft; Big-End And Main Bearing Shells - Opel Kadett Owner's Manual

20.9 Bearing shell tab engages with
groove (arrowed)
holes, while only the centre main bearing cap
half-shells has an oil duct hole.
12 When the shells are fully located in the
crankcase and bearing caps, lubricate them
with clean engine oil (see illustration).
13 Carefully install the crankshaft into
position in the crankcase (see illustration).
14 Lubricate the crankshaft main bearing
journals and then refit the centre main bearing
cap (see illustration). Tighten the retaining
bolts to the specified torque wrench setting.
15 Locate the new oil seal onto the rear end
of the crankshaft, and apply jointing
compound to the block mating flange. Also fill
the grooves on both sides of the rear main
bearing cap with sealant (see illustrations).
16 Fit the rear main bearing cap and tighten
the retaining bolts to the specified torque (see
illustration).
17 Fit the front main bearing cap, but before
20.15a Crankshaft rear oil seal
20.15b Fill the rear main bearing cap
grooves with sealant
20.12 Lubricate the bearing shells
fitting the retaining bolts smear them with
jointing compound and then tighten to the
specified torque wrench setting. Check that
the bearing cap is exactly flush with the end
face of the crankcase as it is tightened.
18 Now rotate the crankshaft and check that
it turns freely, and shows no signs of binding
or tight spots. Check that the crankshaft
endfloat is within the limits specified using a
feeler blade as shown (see illustration). No
provision is made for adjusting crankshaft
endfloat; if it is outside the specified limits, the
most likely reasons are wear or incorrect
regrinding (assuming that the correct shells
have been fitted).
21 Engine components -
examination and renovation

Crankshaft

1 Examine 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.
2 Big-end and crankpin wear is accompanied
by distinct metallic knocking, particularly
noticed when the engine is pulling from low
revs, and some loss of oil pressure.
3 Main bearing and main journal wear is
accompanied by severe engine vibration
rumble - getting progressively worse as
20.16 Fitting the rear main bearing cap
OHV engine 2A•13
20.13 Fitting the crankshaft
20.14 Fitting the centre main bearing cap
engine revs increase - and again by loss of oil
pressure.
4 If the crankshaft requires regrinding take it
to an engine reconditioning specialist, who
will machine it for you and supply the correct
undersize bearing shells.
5 On some engines, the crankshaft journal
diameters are machined
production to allow for greater manufacturing
tolerances.

Big-end and main bearing shells

6 Inspect 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 lead-indium 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.
20.18 Checking the crankshaft endfloat
2A
undersize in