Land Rover 300tdi Diesel Engine Overhaul 1997 Bookmarks Rover Manual

							ENGINE
OVERHAUL19
14.Remove 2 bolts securing engine front lifting
bracket, remove bracket.Valves and springs - remove
1.Support cylinder head clear of valves, use a
hollow drift and tap each valve spring cap to
free collets.
2.Position cylinder head on its side.
3.Using toolLRT-12-034compress valve spring.
4.Remove 2 collets from valve stem.
5.Remove toolLRT-12-034. 
						

							ENGINE
20
OVERHAUL
6.Remove spring cup, valve spring and spring
seat. Keep components in their fitted order.
7.Remove and discard valve stem oil seal.
8.Remove valve, and retain in fitted order.
9.Repeat above procedures for remaining
valves.Cylinder head - inspection
1.Decarbonise cylinder head.
2.Examine cylinder head for cracks, pay
particular attention to area between inlet and
exhaust valve seats. Cracks indicate engine
has overheated and cylinder head must be
replaced.
3.Check core plugs for signs of corrosion and
leakage, replace as necessary.4.Check cylinder head for warping using a
straight edge and feeler gauges.
Maximum warping = 0.08 mm
CAUTION: Cylinder head must not be
refaced, if warping exceeds figure given,
head must be replaced.
5.Check valve seat inserts for burning, pitting or
damage, replace inserts if pitting cannot be
removed by valve lapping-in or refacing. 
						

							ENGINE
OVERHAUL21
Valve springs - inspection
1.Check free length of each spring = 46.28 mm
2.Check that end coils of each spring are square
to body of spring.Valves and guides - inspection
1.Remove carbon from valves.
2.Examine head of each valve for cracks and
burning and valve seat for pitting or burning,
replace valves as necessary.
3.Check valve seating faces for pitting, if light
pitting cannot be removed during valve
grinding operations, valves may be refaced.
CAUTION: If refacing results in valve head
stand down being exceeded, valves must
be replaced.
4.Check valve seating face angles.
Inlet = 60°00 to 60°30 - included angle =120
°
Exhaust = 45°00 to 45°30 - included angle =
90°
5.Reface or replace valves as necessary.
6.Check each valve stem for wear, measure at
each end and centre of valve stem.
Inlet = 7.96 mm
Exhaust = 7.94 mm
7.Replace any valve with stems that are worn. 
						

							ENGINE
22
OVERHAUL
8.Insert a new valve into each guide in turn and
with head of valve positioned 8.0 mm above
seat insert, measure side to side movement of
valve head using a suitable DTI.
Maximum valve head movement = 0.15 mm
9.Replace any valve guide which permits valve
head movement in excess of the above figure.Valve guides - renew
1.Support cylinder head, combustion face
upwards on blocks of wood.
2.Using toolLRT-12-036,drift valve guide out of
cylinder head, discard guide.
3.Clean valve guide bore.
4.Heat cylinder head uniformily to 120°C.
WARNING: Take care when handling
heated cylinder head. 
						

							ENGINE
OVERHAUL23
5.Position cylinder head on bed of hand press.
6.Position replacement valve guide to cylinder
head, ensuring that groove for valve stem seal
is facing away from cylinder head.
7.Position distance piece, toolLRT-12-515and
valve guide replacerLRT-12-046to valve
guide.
8.Press valve guide into cylinder head until
distance piece contacts face of head; remove
tools.
9.Allow cylinder head to air cool.Valve seat inserts - refacing
CAUTION: Prior to refacing valve seats,
check valve head stand down. If, after
refacing, valve head stand down will be
below limits, seat inserts must be replaced.
1.Support cylinder head on its side on suitable
blocks of wood.
2.Loosely assemble pilot, toolLRT-12-502and
a suitable expandable collet, ensuring that
chamfered end of expander is towards the
collet. 
						

							ENGINE
24
OVERHAUL
3.Lightly lubricate the tool with engine oil.
4.Insert pilot into valve guide from combustion
chamber side of cylinder head until shoulder of
pilot contacts guide.
5.Check that collet is fully inserted into valve
guide and expand collet against the guide
using a suitable tommy bar.
6.Assemble the 45°cutter,MS621(exhaust
valves) and 60°cutter,MS627(inlet valves) to
toolLRT-12-501.
7.Position toolLRT-12-501and appropriate
cutter to valve seat insert to be refaced.
8.Using the Allen key, adjust position of cutter so
that centre of cutter contacts area of seat insert
to be cut. 
						

							ENGINE
OVERHAUL25
9.Cut valve seat insert using light hand pressure.
CAUTION: Remove the minimum amount
of material necessary to obtain correct
valve seat face.
10.Smear Prussian Blue to seating face of a
correctly ground valve.
11.Insert valve into guide and press it firmly,
without rotating on to seat insert, remove valve.
12.Check that an even line of Prussian Blue has
been transferred to centre of valve seat insert,
continue cutting operation as necessary until
this has been achieved.
13.Upon completion, remove all traces of swarf.Valve seat inserts - renew
1.Remove original valve seat insert taking care
not to damage cylinder head.
2.Thoroughly clean valve seat insert recess.
3.Heat cylinder head to 65°C.
WARNING: Take care when handling hot
cylinder head.
4.Place cylinder head on bed of hand press and
using a suitable mandrel, press replacement
seat insert into recess.
5.Allow cylinder head to air cool.
6.Check that seat insert is seated squarely in
recess. 
						

							ENGINE
26
OVERHAUL Lapping-in valves
1.Lap each valve to its seat using grinding paste.
2.Apply Prussian Blue to valve seat insert. Insert
valve into guide and press it firmly, without
rotating on to seat.
3.Remove valve and check that a continuous,
even line of Prussian Blue has been
transferred to valve face, continue lapping-in
valve as necessary.
NOTE: Line does not have to be across
whole width of valve face.
4.Remove all traces of grinding paste on
completion.
5.Check valve head stand down of each valve.Valve head stand down - checking
1.Insert each valve into its respective guide.
2.Using a straight edge and feeler gauges, check
and record stand down of each valve head.
3.Compare figures obtained with those given
below. If any valve head has a stand down
outside that specified, valve and/or seat insert
must be replaced.
Valve head stand down:
Inlet valveA= 0.81 to 1.09 mm
Exhaust valveB= 0.86 to 1.14 mm 
						

							ENGINE
OVERHAUL27
Valves and springs - refit
1.Lubricate valve stems, guides, spring seats,
valve springs, spring cups and collets with
engine oil.
2.Lubricate new valve stem oil seals with engine
oil and fit to valve guides.
3.Fit spring seat, insert valve into its respective
guide, fit valve spring and spring cup.
4.Compress valve spring using toolLRT-12-034
and fit collets.
5.Remove toolLRT-12-034.
6.Tap spring cup with a soft mallet to ensure that
collets are correctly seated.
7.Repeat above procedures for remaining
valves.Cylinder head gasket selection
CAUTION: New cylinder head gasket
should be same thickness as the original.
If, however, cylinder head, pistons or
crankshaft have been replaced, it will be
necessary to check piston stand proud in order
to determine the correct thickness of gasket.
1.Position a magnetic base DTI to cylinder block
top face adjacent to number 1 cylinder bore.
2.Position stylus of gauge to cylinder block top
face on edge of number 1 cylinder bore; zero
gauge.
3.Rotate crankshaft in a clockwise direction until
numbers 1 and 4 pistons are at TDC.
4.Position stylus of DTI gauge near edge of
piston crown, measure and record number 1
piston stand proud. Measurement must be
taken at front and rear of piston and highest
protrusion figure recorded.
5.Repeat above procedures for remaining
pistons. 
						

							ENGINE
28
OVERHAUL 6.From all of the readings obtained, determine
highest protrusion figure and select the
appropriate cylinder head gasket.
Protrusion 0.50 to 0.60 mm - select gasket with
1 identification hole.
Protrusion 0.61 to 0.70 mm - select gasket with
2 identification holes.
Protrusion 0.71 to 0.80 mm - select gasket with
3 identification holes.
Protrusion 0.81 to 0.90 mm - select gasket with
0 identification holes.
NOTE: Identification holes are located on
the edge of the gasket.
7.Remove DTI.
8.Rotate crankshaft in a clockwise direction until
all pistons are half-way up cylinder bores.Cylinder head - refit
1.Ensure that mating faces of cylinder head and
block are clean and dry and that 2 locating
dowels are fitted in cylinder block.
2.Lubricate threads of new cylinder head bolts
with engine oil.
3.Check that cylinder head bolt holes in cylinder
block are clean and dry.
4.Rotate crankshaft in a clockwise direction until
pistons are half-way up cylinder bores.
5.Position the selected cylinder head gasket on
cylinder block ensuring that word TOP is
facing upwards.
6.Using assistance, fit cylinder head ensuring
that it is located on dowels.