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Discovery 2. Manual - part 426

ENGINE - TD5

OVERHAUL 12-1-101

11. Repeat above procedures for other pistons in

turn ensuring that pistons and connecting rods
are fitted in cylinder bores from which they
were removed.

12. Fit connecting rod bearings.

ENGINE - Td5, OVERHAUL,

Bearings - connecting rods.

CAUTION: If new pistons, connecting rods
or crankshaft have been fitted, it will be
necessary to select correct thickness of
cylinder head gasket using the following
procedures:

13. There are three thicknesses of cylinder

head gasket available and in order that the
correct gasket is fitted, it is necessary to
determine the stand proud (protrusion) of
each piston above the top face of the
cylinder block. Gaskets have either 1, 2 or 3
identification holes and the following
procedures must be followed in order that
the correct gasket is selected.

14. Temporarily fit and lightly tighten new

crankshaft pulley bolt.

15. Assemble a magnetic base DTI to cylinder

block top face adjacent to No.1 cylinder bore.

16. Position stylus to cylinder block top face and

zero gauge.

17. Using crankshaft pulley bolt, rotate crankshaft

in a clockwise direction until No. 1 piston is at
TDC - Woodruff key slot in crankshaft is at 12
o'clock.

18. Position stylus of DTI at rear edge of piston and

directly over gudgeon pin axis.

19. Measure and record No.1 piston protrusion.
20. Repeat measurement at front edge of piston.
21. Establish average of 2 readings taken.
22. Repeat above procedures for remaining

pistons.

23. From readings obtained, determine HIGHEST

piston protrusion figure and select the
appropriate cylinder head gasket:

Piston protrusion = 0.351 to 0.50 mm (0.014
to 0.02 in) select the 2 hole gasket

Piston protrusion = 0.501 to 0.57 mm (0.021
to 0.022 in) select the 1 hole gasket

Piston protrusion = 0.571 to 0.65 mm (0.022
to 0.025 in) select the 3 hole gasket

24. Remove the DTI.
25. Remove and retain crankshaft pulley bolt.
26. Fit cylinder head gasket.

ENGINE - Td5, OVERHAUL, Gasket

- cylinder head.

ENGINE - TD5

12-1-102 OVERHAUL

Crankshaft

$% 12.21.33.01

Disassembly

1. Remove timing chain and sprockets.

ENGINE - Td5, OVERHAUL, Timing

chain and sprockets.

2. Remove crankshaft rear oil seal.

ENGINE - Td5, OVERHAUL, Seal -

crankshaft - rear - manual models.

3. Remove connecting rod bearings.

ENGINE - Td5, OVERHAUL,

Bearings - connecting rods.

4. Check that cylinder reference number is on

each main bearing cap and make alignment
marks between each main bearing cap and
cylinder block.

5. Starting at No.3 main bearing cap and working

outwards, progressively loosen, then remove 2
bolts securing each cap. Discard main bearing
cap bolts.

6. Fit 2 slave bolts into main bearing cap in turn

and ease bearing caps from cylinder block.

7. Remove and discard plain bearing shells from

each main bearing cap.

8. Using assistance, remove crankshaft.
9. Remove and discard grooved main bearing

shells and 2 thrust washers from cylinder
block.

10. Remove Torx screw securing each oil squirt jet

to cylinder block, remove squirt jets.

11. Clean main bearing shell and thrust washer

locations in cylinder block, ensure bolt holes
are clean and dry.

12. Clean main bearing caps.
13. Clean crankshaft bearing journals, check

oilways are clear.

14. Ensure drillings in oil squirt jets are clear.

ENGINE - TD5

OVERHAUL 12-1-103

15. Check core plugs in cylinder block for corrosion

or signs of leakage, seal replacement plugs
with Loctite 243.

Crankshaft - Inspection

1. Check crankshaft main and big-end bearings

for scoring, wear and ovality, make 3 checks at
120

intervals in centre of journals.

Main bearings = 62.0 mm

0.013 mm

(2.441 in

0.001 in).

Big-end bearings = 54.000 mm

0.01 mm

(2.125 in

0.0004 in).

2. Crankshafts may not be reground, only one

size of main and big-end bearing shell is
available and if journals are found to be
scored, oval or worn, crankshaft must be
replaced. Main and big-end bearing shells
and thrust washers must be replaced
whenever they are removed.

3. Check crankshaft spigot bush for wear, replace

if necessary using the following procedures:

4. Secure crankshaft in a suitably padded vice.
5. Tap a thread in spigot bush to accommodate a

suitable impulse extractor.

6. Fit impulse extractor to spigot bush.
7. Remove spigot bush.
8. Clean spigot bush recess in crankshaft.
9. Fit new spigot bush to crankshaft using a

suitable mandrel.

Reassembly

1. Fit oil squirt jets, fit Torx screws and tighten to

8 Nm (6 lbf.ft).

2. Lubricate new, grooved, main bearing shells

with engine oil and fit to cylinder block.

3. Lubricate new thrust washers with engine oil

and fit, grooved side facing outward, to recess
in each side of No.3 main bearing in cylinder
block.

4. Lubricate crankshaft journals with engine oil

and using assistance, position crankshaft in
cylinder block.

5. Lubricate new, plain, main bearing shells with

engine oil and fit to main bearing caps.