6Before removing the crankshaft, check that
the endfloat is within the specified limits by
inserting a feeler blade between the centre
crankshaft web and one of the thrustwashers
(the thrustwashers are fitted to the crankcase,
not the bearing cap). This will indicate whether
or not new thrustwashers are required.
7Unscrew the bolts, and tap off the main
bearing caps complete with bearing shells.
8Lift the crankshaft from the cylinder block,
and remove the rear oil seal if it is still in place
on the crankshaft.
9Extract the bearing shells, and recover the
thrustwashers, keeping them identified for
location.
Refitting
10Commence refitting as follows(see
illustration).
11Wipe the bearing shell locations in the
crankcase, and the crankshaft journals with a
soft non-fluffy rag.
12If the old main bearing shells are to be
renewed (not to do so is a false economy,
unless they are virtually new) fit the five upper
halves of the main bearing shells to their
locations in the crankcase.
13Fit the thrustwashers to the centre main
bearing location, using a little grease to retain
them if necessary. The oil grooves in the
thrustwashers must face outwards (ie facing
the crankshaft webs). Note that where
standard thrustwashers have been fitted in
production, the centre main bearing is
unmarked. If oversize (0.38 mm)
thrustwashers have been fitted, the centre
main bearing will carry a yellow paint mark.
14Lubricate the crankshaft journals and the
upper and lower main bearing shells with
clean engine oil, then carefully lower the
crankshaft into the crankcase.
15Lubricate the crankshaft main bearing
journals again, and then fit the main bearing
caps in their correct locations, with the arrows
on the caps pointing to the front of the engine.16Fit the main bearing cap bolts, noting that
the studded bolts secure bearing caps Nos 3
and 5.
17Lightly tighten all the securing bolts, then
progressively tighten all bolts to the specified
torque.
18Check that the crankshaft rotates freely.
Some stiffness is to be expected with new
components, but there must be no tight spots
or binding.
19Check that the crankshaft endfloat is
within the specified limits by inserting a feeler
blade between the centre crankshaft web and
the thrustwashers.
20Refit the sump mounting plate to the front
of the cylinder block, and tighten the securing
bolts to the specified torque.
21Carefully wind a thin layer of tape around
the rear edge of the crankshaft, to protect the
oil seal lips as the rear oil seal is installed.
22Refit the crankshaft rear oil seal housing,
using a new gasket, and tighten the securing
bolts to the specified torque.
23Ideally, the new oil seal should be
installed using a tool similar to that used for
fitting the crankshaft rear oil seal. A suitable
tool can be improvised using a metal tube of
suitable diameter, a metal disc or flat bar, and
two flywheel bolts. Draw the seal into position
using the two flywheel bolts. Make sure that
the seal lip faces into the engine.
24With the oil seal installed, carefully pull the
tape from the edge of the crankshaft.
25Refit the pistons and connecting rods.
26Refit the flywheel/driveplate, and the
timing chain and crankshaft sprocket.1Proceed as described in Chapter 2, PartA,
noting the following.
2Production bearing undersizes are
indicated as follows:
Yellow or red paint marks on crankshaft -
standard-diameter main bearing journals.
Green line on crankshaft front counterweight
- main bearing journals 0.25 mm
undersize.
Green spot on counterweight - big-end
bearing journals 25 mm undersize.
1Refer to Chapter 2, PartA, but note that
when the engine is first started, a metallic
tapping noise may be heard. This is due to the
timing chain tensioner plunger assembly
taking time to pressurise with oil, resulting in a
temporarily slack chain. The noise should
stop after a short time, once oil pressure has
built up.
32Initial start-up after overhaul or
major repair
31Crankshaft and bearings -
examination and renovation
2B•18DOHC engine
30.5 Main bearing cap identification mark
(arrowed)
30.10 Crankshaft main bearings and associated components
1 Bearing cap
2 Thrustwasher
3 Stud for oil baffle4 Identification markings
5 Bearing shell without oil
groove6 Bearing shell with oil
groove
7 Bearing seat in cylinder
block
