3239091 - 1028h14 piston connecting rod set - r r
Removing
(
Refitting
)
1. Undo the plug and drain the engine oil. | Recover the engine oil in a suitable
container. |
Rotate the engine through 180° on the
overhauling stand.1. Undo the front and rear bolts (1a) securing the crankcase sump
using tool (1b).
| Name | Country |
|---|
| 1b | Spanner | 1.860.833.001 |
2. Undo the side bolts (2a) securing the crankcase sump using tool
(2b).
| Name | Country |
|---|
| 2b | Spanner | 1.860.834.001 |
3. Cut the crankcase sump sealant using the tool.
| Name | Country |
|---|
| 3 | Blade | 1.870.718.000 |
4. Remove the crankcase sump.
Rotate the crankshaft by means of the toothed
drive pulley screw until the pistons for cylinders 1 and 4 are at
B.D.C.1. Undo the bolts (1a) and remove the connecting rod caps (1b) and
bearing shells (1c) of cylinders no. 1 and no. 4.2. Remove the piston-connecting rod assemblies (2a), complete with
half-bearings (2b) for cylinders 1 and 4.Proceed in the same way when removing the
connecting rod-piston assemblies for the remaining cylinders.
Refitting
(
Removing
)
| Specially-selected main and crankshaft
half-bearings are fitted to this engine to ensure that the matching
clearance is optimum. |
| The crankshaft is supplied, by
the Parts Dept., without the appropriate half-bearings for 'standard'
dimension main journals and crank pins; it is therefore necessary
to select the half-bearings to be fitted by identifying the grade
for each main journal and crank pin for the new crankshaft. |
The following is needed for selecting
the main journal half-bearings
- the code number stamped on the phonic wheel;
- the paint mark, if present, next to the crankpins.
Below is an example of the identification
of crankpin grades.
1 - Crank pin identification number: the
number on the left refers to the first timing side bearing; the
final 'N' is a code that does not matter for 4 cylinder engines.
2 - Main journal identification code: the
first number on the left refers to the first timing side bearing;
the final 'N' is a code that does not matter for 4 cylinder engines.
3 - Set of numbers (if present), in groups
of two digits, which indicate the dimensions (thousandth part) of
the crankpins: the first two numbers on the left refer to the first
pin on the timing side. | Only use the codes in the key,
all other codes on the flywheel should not be used. |
For the identification of the crankpin
grade, refer to the numerical code for reference 1 in the key. In the case of the example, the numbers
2222N indicate that all four bearings are Grade B (blue) as described
belowCRANKPIN IDENTIFICATIONCrankpin grade A (standard), diameter 50.787
50.793 mm, RED paint spot, code number 1 (87 93)* Grade B crankpin (standard), diameter
50.793 50.799 mm, BLUE paint mark, code number 2 (93 99)* Grade C crankpin (standard), diameter 50.799
50.805 mm, YELLOW paint mark, code number 3 (99 05)* Grade D crankpin (0.127mm undersize) diameter 50.660
50.666 mm, BROWN paint mark, code number 6 (60 66)*Grade E crankpin (0.127 mm undersize) diameter 50.666
50.672 mmmm, GREEN paint mark, code 7 (66 72)* Grade F crankpin (0.127 undersize) diameter
50.672 50.678 mm, BLACK paint mark, code number 8 (72 78)*(*) Last two numbers (thousandth part)
of the dimensions of the main journals. If a crankshaft is being used where the
maximum bearing undersize through regrinding is 0.127 mm, then the
grade should be selected by measuring the dimensions of the diameter
of the bearing with reference to the above. Having defined the grade and colour for
each new or reground crankshaft bearing, it is necessary to select the
pair and the size for the bearings which should be the same colour
as the corresponding bearing; at the Parts Dept. it is possible
obtain the part no. of the pair of half-bearings required The above is designed to ensure the optimum
operating clearance for all bearings.Lastly, we wish to point out that, usually,
the clearance between the crankpin and the half-bearing, produced by
the selection method described above, should be 0.030 0.056 mm.
this value can be measured, as a final check, using the Plastic
Gauge as described below. 1. Refit the connecting rod-piston assemblies (1a), complete with
half-bearings (1b), selected as described previously. | Fit the piston-connecting rod
assemblies so that the arrows stamped on the piston crowns face the
exhaust end. |
Turn the crankshaft to gain access to the
big end bearing caps.1. Fit the calibrated wire (Plastigage) to measure the relevant
crankpin clearances.
1. Refit the connecting rod cap (1a), complete with half-bearing,
and secure by tightening bolts (1b) to the recommended torque. | The safety reference marks on
the connecting rod cap and the big end should be on the same side. |
| Fastening | Component | Ø | Value(daNm) |
|---|
| 1b | Bolt | BIG END BEARING CAPS | M9 | 2.4 ÷ 2.6 +60? |
2. Use the tool for angular tightening of the connecting rod cap
bolts.
| Name | Country |
|---|
| 2 | Protractor | 1.860.942.000 |
1. Remove the connecting rod cap fitted previously and, using a
suitable graduated measuring instrument (1a), measure the clearance
shown by the calibrated wire (1b). | Measure the clearance at all the
bearings, taking care to do it one bearing at a time. |
| Measurement | | Value |
|---|
| - | Crankpin/big end bearing play (mm) | | 0.030 ÷ 0.056 |
| If the value measured does not
correspond to the recommended figures, replace the connecting rod
half bearings with ones of a suitable size and grade. |
1. Refit the connecting rod bearing caps (1a), complete with half-bearings
and secure them by tightening bolts (1b) to the recommended torque. | The safety reference marks on
the connecting rod cap and the big end should be on the same side. |
| Fastening | Component | Ø | Value(daNm) |
|---|
| 1b | Bolt | BIG END BEARING CAPS | M9 | 2.4 ÷ 2.6 +60? |
2. Use the tool for angular tightening of the connecting rod cap
bolts.
| Name | Country |
|---|
| 2 | Protractor | 1.860.942.000 |
Clean the contact surfaces of crankcase
sump and cylinder block of sealant residues.Apply silicone sealant around the edge
of the crankcase sump.1. Position the sump on the crankcase.2. Tighten the front and rear bolts (2a) fixing the crankcase sump
to the recommended torque using the tool (2b).
| Fastening | Component | Ø | Value(daNm) |
|---|
| 2a | Front and rear bolts | OIL SUMP | M6 | (Engine crankcase side) 0.8 ÷ 1.0 |
| Name | Country |
|---|
| 2b | Spanner | 1.860.833.001 |
3. Tighten the side bolts (3a) for the crankcase sump to the recommended
torque using the tool (3b).
| Fastening | Component | Ø | Value(daNm) |
|---|
| 3a | Side bolts | OIL SUMP | M8 | (Engine crankcase side) 2.3 ÷ 2.8 |
| Name | Country |
|---|
| 3b | Spanner | 1.860.834.001 |
Tighten the engine oil drain plug to the
crankcase sump to the recommended torque.
| Fastening | Component | Ø | Value(daNm) |
|---|
| - | - | ENGINE OIL DRAIN PLUG | M18 | (Crankcase sump side) 1.8 ÷ 2.2 |
