2.6.7.12 Drive Belt Hum Sound Diagnostic

Diagnostic Tips:

Drive belt should not produce hum sound. If there is an intermittent noise, check the attached parts by changing the load. Make sure
that components run until the maximum load. These conditions may be due to (but are not limited to) over filling the air-conditioning
system, power steering system blocked or steering fluid incorrect, as well as the generator failure.

Fault Definition: Sustained High-Frequency Noise

Step 1

Verify the fault. Does the engine hum appear?

No

To diagnose Tips

Yes

Step 2

Remove the drive belt. Confirm whether the hum sound disappears?

(a)

Remove the drive belt. Refer to 

2.6.8.3

 

Drive Belt

Replacement

.

(b)

Run the engine, but no more than 30 s.

Does the hum sound disappear?

No

Refer to 

2.6.7.4

 

Engine Noise Diagnosis

Yes

Step 3

Check whether all attached drive pulley bearings are normal?

Pulley bearings should not appear stuck, loose and so on.

No

Replace the damaged pulley or bearing.

Yes

Step 4

To diagnostic tips.

2.6.7.13 Drive Belt Off Diagnostics

Diagnostic Tips:

If the drive belt falls off from the pulley repeatedly, the reason may be the pulley misalignment. If the attachment drive belt driving
components cause the load fluctuates, it may cause drive belt fall off from the pulley. Test whether accessories driving parts are
working correctly. If the drive belt's length is not proper, drive belt tensioner will not be able to maintain a suitable drive belt tension.

Fault Definition: Drive belt falls off from the pulley, or incorrectly installed on the pulley.

Step 1

Check the drive belt for damage. If necessary, replace the drive belt.

Next

Step 2

Check whether the pulley is misaligned. Repair the faulty part.

Engine

Engine Mechanical System JL4G18-D

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Next

Step 3

Check whether the pulley is bent or depressed. Repair the faulty part.

Next

Step 4

Check whether the drive belt tensioner device bracket is bent or cracked. Repair the faulty part.

Next

Step 5

Check whether the drive belt tensioner device is working properly. Repair the faulty part.

Next

Step 6

Check whether the attached fasteners loose. Repair the faulty part.

Next

Step 7

Confirm that fault has been fixed.

2.6.7.14 Drive Belt Excessive Wear

Diagnostic Tips:

Drive belt excessive wear and tear is usually due to unreasonable installation or the use of the wrong drive belt. Drive pulley slight
misalignment will not cause excessive wear and tear, but it could lead to drive belt noise or loss. Drive pulley misalignment can
cause excessive wear and can also lead to drive belt fall off.

Fault Definition: The drive belt is not properly installed which led to the drive belt outer edges worn.

Step 1

Check  whether  there  are  frictions  between  drive  belt  and  brackets,  wiring  harness,  hoses  and  other
components?

Yes

Repair the faulty part.

No

Step 2

Check all attachments drive pulley whether there are abnormal scratches on the surface, edges and corners
and other abnormal conditions?

Yes

Repair the faulty part. If necessary, replace
the drive pulley

No

Step 3

Check whether the installed drive belt model is correct?

Yes

Replace the drive belt with a correct type.

No

Step 4

To diagnostic tips.

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Engine

2.6.8 Removal and Installation
2.6.8.1 Plastic Engine Shield Replacement

Removal Procedure:

FE02-0007b

1.

Remove the engine plastic shield retaining nuts.

2.

Remove the plastic engine shield.

Installation Procedure:

FE02-0008b

1.

Install  the  engine  plastic  shield  retaining  nuts  onto  the
engine plastic shield.

2.

Tighten the engine plastic shield retaining nuts.

Torque: 7 Nm (Metric) 5.2 lb-ft (US English)

2.6.8.2 Cylinder Head Cover Replacement

Removal Procedure:

Warning!

Refer to "Battery Disconnection Warning" in "Warnings
and Notices".

Engine

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FE02-0009b

1.

Disconnect  the  battery  negative  cable.  Refer  to

2.11.8.1

 

Battery Disconnection

.

2.

Remove the engine plastic shield. Refer to 

2.6.8.1

 

Plastic

Engine Shield Replacement

.

3.

Remove  the  ignition  coil  and  ignition  wire.  Refer  to

2.10.8.3

 

Ignition Coil Replacement

.

4.

Remove the crankcase ventilation tube.

FE02-0010b

5.

Remove the crankcase ventilation vacuum tube.

FE02-0011b

6.

Remove cylinder head cover bolts and nuts.

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Engine