ROD-PISTON AND CONNECTING
DESCRIPTION
The pistons (2) are of a free floating design. Oil jets in the engine block lubricate and cool the piston and piston pin (1) assembly. The connecting rods (7) have a pressed in place wrist pin bushing which is lubricated by the oil jets. Connecting rod (7) and bearing caps have cracked mating surfaces and are not interchangeable.
STANDARD PROCEDURE - PISTON RING FITTING
1. Wipe cylinder bore clean. Insert ring and push down with piston to ensure it is square in bore. The ring gap measurement must be made with the ring positioning at least 12 mm (0.50 in.) from bottom of cylinder bore. Check gap with feeler gauge (1). Top compression ring gap .30 to .45mm (.0118 to .0177 in.). Second compression ring gap .30 to .45mm (.0118 to .0177 in.). Oil control ring gap .25 to .50mm (.0098 to .0196 in.).
2. If ring gaps exceed dimension given, new rings or cylinder liners must be fitted. Keep piston rings in piston sets.
3. Check piston ring to groove clearance. Top compression ring gap .080 to .130mm (.0031 to .0051 in.) (A). Second compression ring gap .070 to .110mm (.0027 to .0043 in.) (B). Oil control ring gap .040 to .080mm (.0015 to .0031 in.) (C).
REMOVAL
NOTE: Both the connecting rod and the connecting rod cap are paint marked to aid during assembly. Paint marks disappear after time. If the rod and the cap are not marked with paint, paint mark or scribe them before disassembly.
1. Disconnect negative battery cable.
2. Remove cylinder head (Refer to 9 - ENGINE/CYLINDER HEAD - REMOVAL).
3. Raise vehicle on hoist.
4. Remove oil pan (Refer to 9 - ENGINE/LUBRICATION/OIL PAN - REMOVAL).
5. Remove oil pump pickup tube . (Refer to 9 - ENGINE/LUBRICATION/OIL PUMP - REMOVAL).
6. Remove balance shaft assembly (Refer to 9 - ENGINE/VALVE TIMING/BALANCE SHAFT - REMOVAL).
7. Remove top ridge of cylinder bores with a ridge reamer before removing pistons from cylinder block. Be sure to keep top of pistons covered during this operation.
8. Piston and connecting rods must be removed from top of cylinder block. Rotate crankshaft so that each connecting rod is centered in cylinder bore.
NOTE: Be careful not to nick or scratch crankshaft journals
9. After removal, install bearing cap on the mating rod and mark pistons with matching cylinder number when removed from engine block.
PISTON PIN - REMOVAL
1. Secure connecting rods (7) in a soft jawed vice.
2. Remove 2 snap rings (8) securing piston pin (1).
3. Push piston pin (1) out of piston (2) and connecting rod (7).
PISTON RING - REMOVAL
1. ID mark on face of top and second piston rings must point toward piston crown.
2. Using a suitable ring expander, remove top and second piston rings.
3. Remove upper oil ring side rail, lower oil ring side rail and then the oil expander from piston.
4. Carefully clean carbon from piston crowns, skirts and ring grooves ensuring the 4 oil holes in the oil control ring groove are clear.
INSPECTION
PISTONS
1. Piston Diameter: Size: 91.912-91.928mm (3.6185-3.6192 in.) Maximum wear limit .05mm (.0019 in.).
2. Check piston pin bores in piston for roundness. Make 3 checks at 120° intervals. Maximum out of roundness .05mm (.0019in.).
3. The piston diameter should be measured approximately 15 mm (.590 in.) up from the base.
4. Skirt wear should not exceed 0.1 mm (.00039 in.).
5. The clearance between the cylinder liner and piston should not exceed 0.065-0.083 mm (.0025-.0032 in.).
CONNECTING RODS
CAUTION: Connecting rod bolts must be replaced when disassembled. When assembling the connecting rod (2), be sure that the connecting rod pawl (1) on each of the connecting rod caps is facing the rear (fly wheel) side of the engine.
NOTE: Do Not lubricate the new connecting rod bolts. They are already coated with a anti scuff treatment.
1. Assemble connecting rod bearings (4) and bearing caps to their respective connecting rods (2) ensuring that the serrations on the cap and reference marks are aligned.
2. Tighten connecting cap bolts to 10 N·m (88 in. lbs.).
3. Without loosening connecting rod bolts, tighten all bolts to 30N·m (22 ft.lbs.).
4. Using a torque angle gauge, tighten each bolt an additional 40°.
5. Recheck all bolt tightening with a torque wrench set to 88N·m (65 ft.lbs.).
6. Check and record internal diameter of crank end of connecting rod (2).
CAUTION: When changing connecting rods (2), DO NOT use a stamp to mark the cylinder location. Identify the connecting rods (2) and caps location using a paint marker. All four must have the same weight and the same number. Replacement connecting rods (2) will only be supplied in sets of four.
Connecting rods (2) are supplied in sets of four since they all must be of the same weight category. Max allowable weight difference is 5 gr.
PISTON PINS
1. Measure the diameter of piston pin in the center and both ends.For specification, (Refer to 9 - ENGINE - SPECIFICATIONS), (Refer to 9 - ENGINE - SPECIFICATIONS).
INSTALLATION
PISTON PIN INSTALLATION
1. Secure connecting rod (7) in soft jawed vice.
2. Lubricate piston pin (1) and piston (2) with clean engine oil.
3. Position piston (2) on connecting rod (7).
CAUTION: Ensure arrow on piston crown and the bearing cap numbers on the connecting rod are on the opposite side.
4. Install piston pin (1).
5. Install snap ring (3) in piston (2) to retain piston pin (1).
6. Remove connecting rod (7) from vice.
PISTON RINGS - INSTALLATION
1. Install rings on the pistons using a suitable ring expander.
2. Top compression ring is tapered and chromium plated. The second ring is of the scraper type and must be installed with scraping edge facing bottom of the piston . The third is an oil control ring. Ring gaps must be positioned, before inserting piston into the liners, as follows .
3. Top ring gap must be positioned at the #3 position (3) (looking at the piston crown from above).
4. Second piston ring gap should be positioned at the #1 position (1).
5. Oil control ring gap should be positioned at the #2 position (2).
6. When assembling pistons check that components are installed in the same position as before disassembly, determined by the numbers stamped on the crown of individual pistons. Engine cylinders are numbered starting from gear train end of the engine. Face arrow on top of piston toward front of engine. Therefore, the numbers stamped on connecting rod big end should face toward the injection pump side of engine.
INSTALLATION
NOTE: To insert piston into cylinder use a ring compressor (2) as shown.
1. Before installing pistons, and connecting rod assemblies into the bore, be sure that compression ring gaps are staggered so that neither is in line with oil ring rail gap .
2. Before installing the ring compressor (2), make sure the oil ring expander ends are butted together.
3. Immerse the piston head and rings in clean engine oil, slide the piston ring compressor (2), over the piston (1) and tighten. Ensure position of rings does not change during this operation.
4. Face arrow on piston towards front of engine.
CAUTION: Care must be taken not to nick crankshaft journal when installing pistons.
5. Rotate crankshaft so that the connecting rod journal is on the center of the cylinder bore. Insert rod and piston into cylinder bore and guide rod over the crankshaft journal.
6. Guide the piston down in cylinder bore, using a hammer handle. At the same time, guide connecting rod into position on connecting rod journal.
7. Install connecting rod caps. Install rod bolts and torque to 10N·m (88 lbs. in.). Torque bolts the next stage to 30N·m (22 ft.lb.) plus 60°. Then with a torque wrench set at torque to 88N·m (65 ft.lb), make a tightening check.
8. Install cylinder head (Refer to 9 - ENGINE/CYLINDER HEAD - INSTALLATION).
9. Install balance shaft assembly (Refer to 9 - ENGINE/VALVE TIMING/BALANCE SHAFT - INSTALLATION).
10. Install oil pump pickup tube (Refer to 9 - ENGINE/LUBRICATION/OIL PUMP - INSTALLATION).
11. Install oil pan (Refer to 9 - ENGINE/LUBRICATION/OIL PAN - INSTALLATION).
12. Connect negative battery cable.