[11F] ENGINE OVERHAUL <4G69> - - PISTON AND CONNECTING ROD - REMOVAL AND INSTALLATION | PRINT PAGE / INDEX / PRIOR / NEXT

PISTON AND CONNECTING ROD

REMOVAL AND INSTALLATION
|  |  | Removal steps
--- | --- | --- | ---
| >>G<< | 1. | Nut
<<A>> | >>F<< | 2. | Connecting rod cap
| >>D<< | 3. | Connecting rod bearing
| >>E<< | 4. | Piston and connecting rod assembly
| >>D<< | 5. | Connecting rod bearing
| >>C<< | 6. | Piston ring No. 1
| >>C<< | 7. | Piston ring No. 2
| >>B<< | 8. | Oil ring
<<B>> | >>A<< | 9. | Piston pin
|  | 10. | Piston
|  | 11. | Connecting rod
|  | 12. | Bolt
| REMOVAL SERVICE POINTS
| <<A>>CONNECTING ROD CAP REMOVAL
| Mark the cylinder number on the side of the connecting rod big end for correct reassembly. Keep the removed connecting rods, caps, and bearings in that order according to the cylinder number.
| <<B>> PISTON PIN REMOVAL
| The special tool Piston pin setting tool (MD998780), consists of the elements shown in the drawing.
| Insert the tool element, Push rod, into the piston from the front mark side, then attach the element, Guide C, to the push rod. Place the piston and connecting rod assembly on the element, Base, with the front mark facing up. Use a press to remove the piston pin. NOTE: Keep the disassembled pistons, piston pins and connecting rods cylinder by cylinder.
| INSTALLATION SERVICE POINTS
| >>A<< PISTON PIN INSTALLATION
| When replacing a piston, check the cylinder bore size mark stamped at the indicated location on the cylinder block and select an appropriate replacement piston using the following table.
Cylinder bore size mark | Piston size mark
--- | ---
I | A
II | No mark
III | C
NOTE: The piston size mark is located on the piston top surface.
| Measure the following dimensions: A: Piston pin insertion hole length B: Distance between piston bosses C: Piston pin length D: Connecting rod small end width Obtain dimension L from the measurements using the following formula. L =[(A-C) - (B-D)]÷ 2 Insert the tool element, Push rod, into the piston pin and attach the element, Guide A, to the push rod end. Assemble the connecting rod with the piston with their front marks facing in the same direction. Apply engine oil to the outside surface of the piston pin. Insert the assembly of piston pin, Push rod, and Guide A (put together in step 4.) into the piston holes from the front mark side.
| Screw the tool element, Guide B, into the tool element, Guide A until the gap between both the elements is equal to the dimension L (obtained in step 3.) plus 3 mm.
| Place the piston and connecting rod assembly onto the element, Piston setting base, with the front marks facing up. Install the piston pin using a press. If the required press force is less than the standard value, replace the piston and piston pin assembly or the connecting rod, or both. Standard value: 7,350 - 17,100 N
| Check that the piston moves smoothly.
| >>B<< OIL RING INSTALLATION Fit the oil ring spacer into the piston ring groove.
| CAUTION Do not use a piston ring expander when installing side rail. Install the upper side rail. To install the side rail, first fit one end of the rail into the piston groove, then press the remaining portion into position by hand. See illustration. NOTE: The side rails and spacer may be installed in either direction. NOTE: New spacers and side rails are colored for identification of their sizes.
Size | Identification color
--- | ---
Standard | None
0.50 mm oversize diameter | Red
Install the lower side rail in the same manner as described in step 2. Make sure that the side rails move smoothly in both directions.
| >>C<< PISTON RING NUMBER 2/PISTON RING NUMBER 1 INSTALLATION
| Using the piston ring expander, fit number 2 into the number 2 groove of piston. NOTE: Install piston rings with identification mark facing up, to the piston crown side. Install the number 1 piston ring in the same manner as step 1.
| Identification mark: Number 1 ring: None Number 2 ring: 2R NOTE: Confirm the profile for No.1 and No.2 piston rings carefully. Install them correctly by careful attention to the direction of top and bottom. NOTE: The identification mark and the size mark are stamped on the upper plane of the piston ring (piston top side).
Size | Size mark
--- | ---
Standard | None
0.50 mm oversize diameter | 50
To prevent wrong installation, check the identification mark of each piston ring. The identification mark is stamped near the ring gap.
| >>D<< CONNECTING ROD BEARING INSTALLATION
| Measure the crankshaft pin diameter and confirm its classification from the following table. On a crankshaft supplied as a service part, identification marks of its pins are stamped at the positions shown in the illustration.
Crankshaft pin outside diameter | Connecting rod bearing
--- | ---
Identification mark | Size mm | Identification mark
I | 44.995 - 45.000 | 1
II | 44.985 - 44.995 | 2
III | 44.980 - 44.985 | 3
If the crankshaft pin outside diameter identification mark is "I," for example, select a bearing whose identification mark is "1." If there is no identification color paint on the crankshaft, measure the pin outside diameter and select a bearing appropriate for the measured value. Install the selected bearing in the big end and in the cap of the connecting rod.
| >>E<< PISTON AND CONNECTING ROD INSTALLATION
| Apply engine oil on the circumference of the piston, piston rings, and oil ring. Arrange the piston ring and oil ring gaps (side rail and spacer) as shown in the illustration. Rotate the crankshaft so that the crank pin is on the center of the cylinder bore.
| Use suitable thread protectors on the connecting rod bolts before inserting the piston and connecting rod assembly into the cylinder block. Care must be taken not to nick the crank pin. Insert the piston and connecting rod assembly into the cylinder with the front mark on the piston crown pointing to the timing belt side. Using a suitable piston ring compressor tool, install the piston and connecting rod assembly into the cylinder block.
| >>F<< CONNECTING ROD CAP INSTALLATION
| Verifying the mark made during disassembly, install the bearing cap to the connecting rod. If the connecting rod is new with no index mark, make sure that the bearing locking notches are on the same side as shown.
| Make sure that the connecting rod big end side clearance meets the specification. Standard value: 0.10 - 0.25 mm Limit: 0.4 mm
| >>G<< CONNECTING ROD CAP NUT TIGHTENING The connecting rod bolts should be examined before reuse. If the bolt threads are damaged, the bolt should be replaced. Hand-thread the nut to the full length of the bolt threads. If the nut does not run down smoothly, the bolt should be replaced. Before installing each nut, apply engine oil to the threaded portion and bearing surface of the nut. Loosely tighten each nut to the bolt. Then tighten the nuts alternately to the specified torque to install the cap properly. Tightening torque: 20 ± 2 N·m
| Make a paint mark on the head of each nut. Make a paint mark on the bolt end at the position 90 to 94 degrees from the paint mark made on the nut in the direction of tightening the nut. CAUTION If the nut is turned less than 90 degrees, proper fastening performance may not be achieved. Be careful to tighten the nut exactly 90 degrees. If the nut is overtightened (exceeding 94 degrees), loosen the nut completely and then retighten it by repeating the tightening procedure from step 3. Turn the nut 90 to 94 degrees and make sure that the paint marks on the nut and bolt are aligned.

[11F] ENGINE OVERHAUL <4G69> - - PISTON AND CONNECTING ROD - REMOVAL AND INSTALLATION | PRINT PAGE / INDEX / PRIOR / NEXT

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