No

Step 6

Check whether there are excessive cam wear or obvious fults?

Yes

Repair the faulty part. Refer to

2.6.8.12

 

Camshaft Replacement

No

Step 7

Check valve for the existence of cracks, excessive wear and tear and other faults?

Yes

Repair the faulty part. Refer to

2.6.8.15

 

Cylinder Head Assembly Removal

and Installation

No

Step 8

Check valve spring seating and the valve spring washer. Is the installation incorrect?

Yes

Repair the faulty part. Refer to

2.6.8.15

 

Cylinder Head Assembly Removal

and Installation

No

Step 9

Confirm whether the fault is fixed.

2.6.7.9 Drive Belt Inspection

Worn Aging Timing Chain

Timing Chain Installation

Proper Meshing

FE02-7000b

Engine

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1. Inspect when the engine is cool or has been turned off for 30 min.

2. Visual Inspect whether there is V-drive belt excessive wear or cord wear. If faults are found, replace the V-drive belt.

3. Visual Inspect whether there is drive belt inner or outer damage, wear and cracks. If faults are found, replace the drive belt.

4. If no faults are found in steps 2 and 3, measure the drive belt tension: rotate crankshaft pulley two laps clockwise and measure

whether the tension is even along the drive belt tensioner pulley.

5. Use sound pressure meter (General Maintenance Tools) to measure drive belt tension and frequency at the marked point A.

 

New Drive Belt

Old Drive Belt

Drive Belt Tension (N / lb)

400-500/89.9-112.4

300-400/67.4-89.9

a. Replace with new drive belt. Rotate the crankshaft two laps clockwise, so that the drive belt completely runs through the drive

pulley. Measure the tension at marked position A. Refer to the table and replace the drive belt if the measurement is beyond the
scope of the table.

b. If the used drive belt tension is beyond the scope of the table, replace it with a new drive belt.

c. During the drive belt installation, please make sure the correct installation to the drive pulley groove.

d. Do not drop engine oil or engine coolant onto the drive belt.

e. Do not over-wind or bend the drive belt.

2.6.7.10 Drive Belt Chirp Sound Diagnostic

Diagnostic Tips:

The symptom may be due to wet drive belt or pulley and may be an intermittent fault. Drive belt may need to spray a small amount
of water to reproduce customer reported fault. If the symptom reoccurs after spraying water, then clean the pulley. Body parts,
suspension parts or other vehicle parts loose or unreasonable installation can also cause the chirp sound.

Fault Definition: The following conditions are the drive belt chirp sound symptoms

–

A chirp jack noise can be heard once rotate the drive belt a lap.

–

Noise often happens on a rainy day or in a cold morning.

Step 1

Verify the fault. Does the engine have chirp sound?

No

To diagnose Tips

Yes

Step 2

Remove the drive belt. Confirm whether the 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 chirp sound disappear?

No

Refer to 

2.6.7.4

 

Engine Noise Diagnosis

Yes

Step 3

Check whether the drive belt surface is normal? (Balls and cracks, etc?)

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Refer to 

2.6.7.9

 

Drive Belt Inspection

No

Replace the drive belt. Refer to 

2.6.8.3

 

Drive

Belt Replacement

Yes

Step 4

Check whether the drive pulley is installed correctly? (Misaligned, etc?)

No

Reinstall the drive pulley, if necessary,
replace the drive belt.

Yes

Step 5

Check whether the drive pulley is normal?

Check whether the pulley is bent, twisted and so on.

No

Replace the failed pulley.

Yes

Step 6

Check whether all fasteners associated with the drive belt are normal?

No

Tighten loosen fasteners.

Yes

Step 7

Replace the drive belt. Confirm the fault is fixed.

2.6.7.11 Drive Belt Scream Diagnostic

Diagnostic Tips:

Body, suspension and other components loose or unreasonable installation may cause screams. If there is intermittent noise, check
the attached parts by changing the engine load. Check whether the air-conditioning system is over filled, power steering hose is
clamped, the power steering fluid is correct or whether the generator is faulty.

Fault Definition: The following conditions are the drive belt screams symptoms

–

Drive belt screams due to slippage.

–

Noise appears when a big load added to the drive belt, such as air-conditioning system compressor starting, the running engine
with the throttle quickly opening or drive belt skidding in a drive component.

Step 1

Verify the fault. Does the engine scream?

No

To diagnose Tips

Yes

Step 2

Remove the drive belt. Confirm that the scream 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.

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Does the scream 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 do not appear stuck, loose and so on.

No

Replace the damaged pulley or bearing.

Yes

Step 4

Check whether drive belt tensioner device is working properly?

Tensioner pulley bearing device does not appear stuck, loose.
Tensioner device does not appear loose and other damages.

No

Replace the drive belt tensioner assembly.
Refer to the

2.6.8.4

 

Drive Belt Tensioner

Replacement

Yes

Step 5

Check whether the correct drive belt is used?

Check whether the drive belt is stretched. Refer to 

2.6.7.9

 

Drive Belt

Inspection

.

No

Replace the drive belt. Refer to 

2.6.8.3

 

Drive

Belt Replacement

Yes

Step 6

Check all fasteners associated with the drive belt are normal?

No

Tighten loose fasteners.

Yes

Step 7

Check whether drive pulley is normal?

Check whether the pulley is bent, twisted and so on.

No

Replace the failed pulley.

Yes

Step 8

To diagnostic tips.

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