Page 2473 of 4264
ENGINE MECHANICAL (C24SE) 6A-53
4. Heat a new con-rod to 280
C in the oil bath.
5. Install the con-rod to the piston and insert the piston pin.
Important!
Since the con-rods have no weight balancing studs, re-working
is not possible.
Exchange con-rods in sets only.
Installation position, beads on con-rod point to the flattening on
the piston pin eye.
Firmly seated piston pin cannot be pushed in. Carry out
installation quickly.
Piston Rings
Removal
1. Remove piston with con-rod according to the
corresponding operation.
2. Remove piston rings using commercially available ring
installer or piston ring clamp pliers.
Clean
Piston ring grooves - ground piece of old piston ring
Inspection
Piston ring gap
For piston ring sizes, permissible piston ring gaps - see
"Technical Data"
Page 2474 of 4264
6A-54 ENGINE MECHANICAL (C24SE)
RTW46ASH002401
Installation
1. Install oil scraper ring.
2. Offset ring gaps of steel band rings each 25 to 50 mm/1
to 2in. to the left or right of the intermediate ring gap.
3. Install piston rings.
4. Offset ring gaps by approx. 180
.
5. Install second piston ring with identification mark "TOP"
facing upwards.
6. Install piston with con-rod according to the corresponding
operation.
Page 2475 of 4264

ENGINE MECHANICAL (C24SE) 6A-55
OPERATIONS ON REMOVED ENGINE
Crankshaft
Removal
1. Mount the engine on an engine overhaul stand with
appropriate adapters.
2. Remove the aggregates, flywheel/drive disc, oil pan,
bearing bridge and oil pump according to the
corresponding operation.
3. Mark the con-rod bearing cover.
4. Remove the crankshaft bearing cover.
5. Remove the crankshaft from cylinder block.
Inspection
Remove and install all parts if necessary.
Crankshaft pulse pickup sensor rotor inspection and repair.
Inspect the crankshaft pulse pickup sensor rotor for excessive
wear and damage.
Replace the crankshaft pulse pickup rotor if the inspection
results exceed wear and damage limits.
Installation
1. Install the crankshaft pulse pickup sensor.
Torque: 13N
m (1.3 kgf
m)
2. Install new bearing shells into the cylinder block and
bearing cover.
3. Coat the bearing shafts with engine oil.
For oversizes-see “Technical Data”
4. Install a new crankshaft into the cylinder block.
Note
The sealing of the crankshaft can be corrected with light
blows with a rubber hammer on the crank arm (arrowed).
Page 2476 of 4264

6A-56 ENGINE MECHANICAL (C24SE)
5. Apply a bead of sealant (TB-1207C or equivalent) in the
grooves of both bearing shells.
Important!
After installation of bearing cover, press in sealing compound
again from above, until compound emerges at the joints.
Torque - Angle Method
Bearing cover to cylinder block - 50 Nm (5.1 kgfm) +40 to
50
Con-rod bearing cover to con-rod - 35 N
m (3.5 kgf
m) +45
to
60
.
Use new bolts.
6. Install oil pump, oil pan, bearing bridge rear crankshaft
sealing, flywheel/drive plate, and aggregates according to
the corresponding operations.
Inspection
Bearing play - bearing cover removed
Measure
With "Plastigage" (ductile plastic threads)
Cut threads to length of bearing width and lay axiaity between
crankshaft journal and bearing shell (arrowed).
Install bearing cover with correct torque.
Important!
Grease crankshaft journal and lubricate bearing shell slightly
so that the thread does not tear when the bearing cover is
moved.
Crankshaft
Inspection
End play when bearing shells are installed.
Front end contact surfaces of flywheel/flexible plate.
Permissible end play - see "Technical Data "
Page 2477 of 4264

ENGINE MECHANICAL (C24SE) 6A-57
Inspection
Out-of-round (run-out)-middle bearing shell removed when
mounting on front and rear bearing.
Permissible out-of-round - see "Technical Data"
Bearing Free Play Measurement
Two methods for measuring bearing free play are described -
1. Plastigage method and 2. micrometer and gauge method.
The two procedures are suitable for measuring both con-rod
and main bearing free play.
For both methods ensure con-rod and main bearing caps are
identified (1) prior to removal as they are machine matched.
1.Plastigage Method
Removal
1. Remove bearing cap and shell.
2. Lightly coat journals and bearings with engine oil to
prevent Plastigage from tearing when cap is removed.
Installation
1. Lay a length of Plastigage across width of crank pin and
fit bearing cap and shell using old bolts at this stage.
Important!
Do not allow crankshaft to rotate.
Torque - Angle Method
Main bearing cap bolt - 60 N
m (6.1 kgf
m) +40
+ to 50
.
Con-rod bearing cap bolts - 35 N
m (3.6 kgf
m) +45
.
Removal
1. Remove bearing cap and shell.
Measure
Width of Plastigage -use scale supplied with Plastigage.
If con-rod bearing clearance exceeds 0.031mm/0.001in or
main journal bearing clearance exceeds 0.04mm/0.02in. -
check crankshaft journal diameters - see corresponding
operation.
Replace bearing if crankshaft is within specification - see
"Technical Data"
Page 2478 of 4264

6A-58 ENGINE MECHANICAL (C24SE)
Clean
Plastigage from journals.
Lightly coat journals and bearings with engine oil.
Installation
Install bearing cap and shell using new bolts.
Torque - Angle Method
Main bearing cap bolt - 60 N
m (6.1 kgf
m) +40
to 50
.
Con-rod bearing cap bolts - 35 N
m (3.9 kgf
m) +45
.
2.Micrometer and gauge method.
Crankshaft removed.
Installation
1. Install caps and bearing shells to con-rods and cylinder
block.
Measure
Con-rod and main bearing diameters at three points I, II, III
(arrowed).
Divide the sum of the three measurements by three to obtain a
mean diameter.
The top illustration shows con-rod measuring points.
The second illustration shows main bearing measuring points.
Measure
Crankshaft main and con-rod bearing journals at points I and
II. Divide the sum of both measurements to obtain a mean
diameter.
Crankshaft must be replaced if mean diameter of main or con-
rod journals is below specified limit - see "Technical Data".
If crankshaft is serviceable subtract crankshaft mean journal
diameters from corresponding shell bearing mean diameters to
determine bearing clearance.
Permissible main bearing clearance - 0.015 to 0.04mm/0.0006
to 0.002in.
Permissible con-rod bearing clearance - 0.006 to
0.031mm/0.002 to 0.001in.
Page 2479 of 4264

ENGINE MECHANICAL (C24SE) 6A-59
Bypass Valve
Removal
1. Remove oil filter.
2. Remove bypass valve by cutting thread in locking disc
with M 10 tap (3rd stage), turning in M 10 bolt and taking
out bypass valve from seating.
Installation
1. Install bypass valve using drift (diameter approx.
15mm/0.6in.).
Oil Filter
Removal
1. Remove oil filter using commercially available tool.
Installation
1. Install oil filter by hand and oil seal ring.
2. Fill up engine oil while preventing overflow.
Oil Pump
Removal
1. Remove rear toothed belt cover, and oil pan according to
the corresponding operations.
2. Remove oil filter, wiring plug from oil pressure switch, oil
pump from cylinder block, and oil pressure switch from
oil pump.
Clean
Sealing surfaces
Installation
1. Install oil pressure switch to oil pump, oil pump to cylinder
block, oil pan, bearing bridge wiring plug, oil filter and
toothed belt cover.
Tighten (Torque)
Oil pressure switch to oil pump - 30 N
m (3.2 kgf
m)
Oil pump to cylinder block - 6 N
m (0.6 kgf
m)
Oil intake pipe to oil pump - 8 N
m (0.8 kgf
m)
Intake pipe bracket to cylinder block - 8 N
m (0.8 kgf
m)
*Insert bolts with Locktite (Refer to General Description
Recommended Liguid Gasket)
Page 2480 of 4264
6A-60 ENGINE MECHANICAL (C24SE)
Oil Pump Safety Valve
Removal
1. Remove closure plug.
2. Remove seal ring.
3. Remove spring.
4. Remove piston.
Installation
1. Install piston (observe installation position).
2. Install spring.
3. Install seal ring.
4. Install closure plug.
Tighten (Torque)
Closure plug - 30 N
m (3.0 kgf
m)
Oil Pump (Overhaul)
Removal
1. Remove oil pump according to the corresponding
operation.
2. Remove oil cover and pressure control valve.
Inspect
Clearance between gear pair and housing upper edge - see
“Technical Data”.
Check housing, cover and pressure control valve.
Installation
1. Install pump cover with Sealing Compound 15 03 166 (90
094 714).
2. Install oil pump safety valve according to the
corresponding operation.
3. Install oil pump according to the corresponding operation.