Piston group — removal and installation (Freelander 1)

Contents: Dismantling ⇩ Installation ⇩

Dismantling

1. Disconnect the negative battery terminal.

2. Remove the cylinder head gasket.

3. Remove the connecting rod bearings.

4. Remove carbon deposits from the top of the cylinder.

5. Carefully knock the piston out of the cylinder.

6. To prevent the timing chain from jamming when the crankshaft rotates, you may need the help of a partner.

7. Repeat the above operations with the remaining three pistons.

8. Clamp the connecting rod in a vice with soft jaws.

8. Clamp the connecting rod in a vice with soft jaws.

9. Using two thin screwdrivers, carefully remove and discard the two piston ring retaining rings.

10. Push the piston pin out of the piston and connecting rod and remove the piston.

11. Pistons and cylinders: Measure the cylinder diameter in the lower, middle and upper belts in the plane shown in the figure. Record the measurement results.

TECHNICAL SPECIFICATIONS, Engine - Diesel Td4.

12. Repeat the measurement in the plane shown in the figure and, using two groups of measurements, calculate the ovality and taper of the cylinder.

13. Starting with piston No.1, measure the skirt diameter in the plane perpendicular to the piston pin axis, at a distance of 12 mm from the lower edge of the skirt:

14. Compare the piston diameter with the cylinder diameter and calculate the gap between the piston and the cylinder.

15. Remove the compression rings, composite oil scraper rings and oil scraper ring expander from the new piston.

16. Insert new rings into the cylinder and check the mounting clearance in them at a distance of 30 mm from the upper plane of the block. When measuring the clearance, make sure that the rings are in a plane perpendicular to the cylinder axis.

17. Install the oil scraper rings and expander, making sure that the rings are flush and do not overlap.

18. Place the second compression ring with the 'TOP' mark facing up.

19. Place the top compression ring with the 'TOP' mark facing up.

19. Place the top compression ring with the 'TOP' mark facing up.

20. Check the clearance between the ring and the piston groove.

21. Check the fit of the piston pin in the piston: the pin should move with little effort, without jamming or noticeable play.

22. Check the wear of the connecting rod upper head bushing, check the fit of the pin in the bushing: the pin should move with little effort, without jamming or noticeable play.

23. Check that the connecting rod is not deformed. Install a new bearing with a running-in layer, marked BLUE, into the connecting rod. Install a new bearing, marked RED, into the connecting rod lower head cap.

24. Install the caps on the connecting rods, screw the old bolts back into place and tighten them to a torque of 5 Nm.

24. Install the caps on the connecting rods, screw the old bolts back into place and tighten them…

25. Check the parallelism of the axes of the upper and lower heads of the connecting rods by taking measurements at a distance of approximately 150 mm from the plane of symmetry of the connecting rod.

26. Check that there is no deformation on either side of the connecting rod.

Installation

1. Wipe the cylinder bore, pistons, piston rings and connecting rods.

2. Place the pistons on your connecting rods, making sure the number on the small end of the connecting rod is aligned with the arrow on the piston crown as shown in the picture.

3. Lubricate the piston pins, piston bores and connecting rod upper heads with engine oil. Insert the piston pins and secure them with new retaining rings, which must be fully seated in their grooves.

4. Lubricate the pistons, piston rings and cylinder bore with clean engine oil.

5. Check the freedom of movement of the rings in their grooves. Spread the ring joints 120° relative to each other so that the joints are not on the most loaded side of the piston (the left side of the piston when looking at its front).

5. Check the freedom of movement of the rings in their grooves. Spread the ring joints 120°…

6. Using the LRT-12-204 tool, compress the piston rings.

7. Install the LRT-12-176 guides onto the connecting rod to protect the cylinder bore and crankpin.

8. Insert the piston into the cylinder so that the arrow on the bottom of the piston points towards the front of the engine.

9. Remove the LRT-12-176 guides from the connecting rods.

10. Install the connecting rod bearings.