Disassembling the cylinder block [Toyota Land Cruiser J70]

Contents: Only KZ engine ↓ All engines ↓ L Series ↓ KZ Series ↓ Connecting Rod Bearing Insert…↓ L Series ↓ KZ Series ↓ Main Bearing Shell Selection Table ↓

1. Loosen the mounting bolts and remove the rear oil seal holder.

Only KZ engine

2. Checking the axial clearance of the balance shaft

Measure the axial clearance using a dial indicator.

Nominal clearance - 0.065 - 0.14 mm
Maximum gap - 0.25 mm

If the gap is greater than the permissible value, replace the shaft thrust flange or the shaft itself.

3. Dismantling the balance shafts,

a) Unscrew the two bolts securing the thrust flange and remove the shaft.

b) Clamp the shaft in a vice by the counterweight, unscrew the drive gear mounting bolt, remove the gear and thrust flange.

All engines

2. Measure the connecting rod axial clearance by moving the connecting rod along the journal.

Nominal axial clearance:

series L - 0.08 - 0.30 mm
kZ series - 0.10 - 0.30 mm

Maximum axial clearance:

l series - 0.35 mm
kZ series - 0.40 mm

If the axial clearance exceeds the maximum permissible value, replace the connecting rod. If necessary, replace the crankshaft.

3. Remove the lower connecting rod head caps and check the clearance in the connecting rod journals.

a) Using a center punch or digital stamp, make alignment marks on the connecting rod and cap to ensure proper assembly.

b) Unscrew the nuts securing the connecting rod caps.

c) Use a plastic hammer to tap the bolts and remove the connecting rod caps.

Note: Leave the connecting rod bearings in place.

d) Cover the connecting rod bolts with small pieces of hose to protect the crankshaft from damage.

d) Clean the crank journal and bearing.

e) Check the crankpin and bearing for chipping and cracks. If the crankpin or bearing is damaged, replace the bearing shells. If necessary, grind or replace the crankshaft.

g) Place a piece of plastic gauge along the axis of the crank pin.

h) Install the connecting rod lower end cover and tighten to a tightening torque of 54 N·m (L series) or 29 N·m (KZ series), and tighten the bolts by 90°.

Note: Do not turn the crankshaft.

i) Remove the lower connecting rod head cover.

k) Measure the size of the gauge at the point of maximum width, determine the gap.

Nominal clearance:

Series L 0.036 - 0.064 mm
Series KZ 0.036 - 0.054 mm

Clearance in repair liners:

Engine 2L 0.023 - 0.073 mm
Engine 3L 0.033 - 0.079 mm
Engine KZ 0.037 - 0.077 mm

Maximum gap: 0.10 mm

If the clearance exceeds the maximum permissible value, grind or replace the crankshaft.

Note: If nominal size bearings are installed, the bearing can be replaced with a bearing that has the same number, the marking of which is applied to the lower connecting rod head cover.
Standard bearing has dimensions marking:

"1", "2" and "3" - L series

"2", "3","4","5" and "6" - KZ series

L Series

Bearing insert thickness of nominal size:

Marking "1" - 1.478 - 1.482 mm
Marking "2" - 1.482 - 1.486 mm
Marking "3" - 1.486 - 1.490 mm

KZ Series

Connecting rod lower head diameter:

Marking "1" - 62.014-62.020 mm
Marking "2" - 62.020-62.026 mm
Marking "3" - 62.026-62.032 mm

Crankpin diameter:

Marking "1" - 58.994-59.000 mm
Marking "2" - 58.988-58.994 mm
Marking "3" - 58.982-58.988 mm

Bearing insert thickness of nominal size:

Marking "2" 1.486 - 1.489 mm
Marking "3" - 1.489 - 1.492 mm
Marking "4" 1.492 - 1.495 mm
Marking "5" - 1.495 - 1.498 mm
Marking "6" - 1.498 - 1.501 mm

Note: The selection of the connecting rod bearing shell is carried out according to the table.

l) Completely remove any remaining gauge.

4. Remove the connecting rod and piston group.

a) Remove carbon deposits from the top of the cylinder.

b) Push the connecting rod-piston group and the upper bearing shell through the top side of the cylinder block.

Reminder: Keep the bearings (liners), connecting rod and cap together. Arrange the piston and connecting rod assemblies in the order of removal.

5. Measure the axial clearance by moving the crankshaft back and forth using a screwdriver acting as a lever.

Nominal axial clearance - 0.1 - 0.3 mm
Maximum axial clearance - 0.4 mm

If the axial clearance exceeds the maximum allowable value, replace the thrust bearing.

Thickness of thrust half rings:

Nominal - 2.430 - 2.480 mm
Repair No.1 - 2.493 - 2.543 mm
Repair No.2 - 2.555 - 2.605 mm

6. Remove the main bearing caps and check the main journal-to-bearing clearance.

a) Remove the ten main bearing cap bolts.

b) Using the removed main bearing cap bolts, move the main bearing cap back and forth, then remove the main bearing caps, lower main bearing shells and lower thrust washers (L series in bearing No.3, KZ series in bearing No.5).

Note: Keep the lower main bearing shell and main bearing cap together.

Arrange the main bearing caps and lower thrust washers in the order of removal.

Connecting Rod Bearing Insert Selection Table

c) Raise the crankshaft.

Note: Keep the upper main bearing shells and upper thrust washers together with the cylinder block.

d) Clean the journal and shell of each main bearing.

d) Check the journal and shell of each main bearing for chipping and cracks. If the journal or shell is damaged, replace the bearing shells. If necessary, grind or replace the crankshaft.

e) Install the crankshaft on the cylinder block.

g) Place a plastic gauge on each neck.

h) Install the main bearing caps and tighten to a torque of 103 N·m for the L series, 49 N·m for the KZ series, in two steps, and then turn an additional 90 degrees.

Note: Do not turn the crankshaft.

i) Remove the main bearing caps.

k) Measure the size of the gauge at the point of maximum width, determine the gap.

Nominal clearance:

series L - 0.034 - 0.065 mm
kZ series - 0.036 - 0.054 mm

Clearance in repair bearing:

series L - 0.033 - 0.079 MM
kZ series - 0.037 - 0.077 mm

Maximum gap - 0.10 mm

If the clearance exceeds the maximum permissible value, replace the bearing shells. If necessary, grind or replace the crankshaft.

Note: If nominal size bearings are installed, the bearing must be replaced with a bearing that has the same number, the marking of which is located on the rear lower right side of the cylinder block. The standard bearing is marked "1", "2" and "3" (L series) or "2", "3", "4", "5" and "6" (KZ series).

L Series

Nominal size liner thickness:

Marking "1" - 1.979 - 1.983 mm
Marking "2" - 1.983 - 1.987 mm
Marking "3" - 1.987 - 1.991 mm

KZ Series

Shaft bed diameter in block:

Marking "1" - 75.000-75.006 mm
Marking "2" - 75.006-75.012 mm
Marking "3" - 75.012-75.018 mm

Main journal diameter:

Marking "1" - 69.994-70.000 mm
Marking "2" - 69.988-69.994 mm
Marking "3" - 69.982-69.988 mm

Nominal size liner thickness:

Marking "2" - 2.479-2.482 mm
Marking "3" - 2.482-2.485 mm
Marking "4" - 2.485-2.488 mm
Marking "5" - 2.488-2.491 mm
Marking "6" - 2.491-2.494 mm

Main Bearing Shell Selection Table

The selection of the main bearing shell is carried out according to the table

l) Completely remove any remaining gauge.

7. Remove the crankshaft.

a) Raise the crankshaft.

b) Remove the upper main bearing shells and upper thrust half rings from the cylinder block.