Isuzu KB P190. Manual — part 355

6A-60 ENGINE MECHANICAL (4JK1/4JJ1)

Removal

1. Rotate the crankshaft to make the No. 1 cylinder

meet the compression TDC.

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Legend

1. TDC

2. Remove the engine cover.

3. Remove the cylinder head cover.

Refer to "Cylinder Head Cover".

4. Install the M5 lock bolt of fixing sub gear.

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5. Remove the baffle plate (1).

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6. Remove the camshaft bearing cap and camshaft.

• Check the engraved making on the camshaft

bearing caps.

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ENGINE MECHANICAL (4JK1/4JJ1) 6A-61

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Disassembly

1. Remove the sub gear assembly.

• Clamp the camshaft in a vise. Insert soft metal

protectors (aluminum) between the vise

surfaces and the camshaft.

• Use 5-8840-2591-0 to turn sub gear to right

direction to remove the M5 bolt.

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• Use a pair of snap ring pliers to remove the

scissor gear assembly.

Note:
Take care not to damage the camshaft cams and
journals.

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2. Remove the camshaft gear.

• Use a press (1) and socket (2) to remove the

camshaft gear (3).

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6A-62 ENGINE MECHANICAL (4JK1/4JJ1)

3. Remove the dowel pin.

4. Inspect the camshaft visually.

• Check if the journal and cam parts of the

camshaft are worn or damaged, if so, replace

it.

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5. Inspect an end clearance of the camshaft.

• Use a thickness gauge to measure an end

clearance of the camshaft gear and the

camshaft bracket.

• If the measurement exceeds the limit, replace

the camshaft gear or the camshaft.

End clearance of the camshaft

mm (in)

Standard 0.085

− 0.205 (0.003 − 0.008)

Limit 0.25

(0.010)

Note:
Measure an end clearance of the camshaft before
disassembling.

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6. Check if the cam lobe is worn.

• Use a micrometer to measure the height of the

cam lobe.

• If the height of the cam lobe is at the limit or

less, replace the camshaft.

Height of the cam lobe

mm (in)

Inlet

Exhaust

Standard

40.6 (1.60)

40.6 (1.60)

Limit

39.6 (1.56)

39.6 (1.56)

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7. Check if the camshaft journal is worn.

• Use a micrometer to measure wear which is

not even with a diameter of the camshaft

journal.

• If the measured uneven wear exceeds the limit,

replace the camshaft.

External diameter of the camshaft journal part

mm (in)

Standard 29.909

− 29.930

(1.1775

− 1.1783)

Limit 29.809

(1.1736)

Partial wear of the camshaft journal part

mm (in)

Limit 0.05

(0.0020)

ENGINE MECHANICAL (4JK1/4JJ1) 6A-63

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8. Check if the camshaft is runout.

• Place the camshaft on a V block to measure a

runout with a dial gauge.

• Rotate the camshaft slowly to measure how

much the dial indicator shook. If it exceeds the

limit, replace the camshaft.

Runout of the camshaft

mm (in)

Limit 0.05

(0.0020)

LNW21BSH020601

9. Measure a camshaft journal oil clearance.

a. Measure an inside diameter of the camshaft

bearing with a dial gauge.

b. Read the difference between the inside

diameter of the camshaft bearing and the

diameter of the camshaft journal.

If the measured oil clearance exceeds the limit,

replace the camshaft bearing.

Clearance of the journal part

mm (in)

Standard

0.025

− 0.087

(0.0010

− 0.0034)

Limit 0.15

(0.0059)

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Reassembly

1. Install the dowel pin.

2. Install the camshaft gear.

• Align the knock pin with the slot in the camshaft

gear. Use a press to install the camshaft gear

to the camshaft.

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Legend

1.

Camshaft

2.

Dowel

Pin

3.

Camshaft

Gear