Engine - Slight Oil Leak/Metallic Tapping Noise
B005/98CAMSHAFT FRICTION GEAR NOISE
Note:
This bulletin supersedes the following TSB(s): B006/97. Please update your records accordingly.
APPLICABLE MODELS/VIN
1992-94 MX-3 with a K-8 engine
1993-97 626/MX-6 with a KL engine
1995-97 Millenia with a KL engine with a VIN of JM1TA22**V1305669 and lower.
DESCRIPTION
A metallic tapping noise may be heard from the right (rear) cylinder head exhaust cam area. The sound is most likely to be heard when the engine is at normal operating temperature and running at 1200 rpm. Review the noise comparison chart below for a description of typical engine noises.
The noise is caused by reduced friction torque between the camshaft friction gear and the cam shaft driven gear.
To correct this condition at mass production, the contact surface between the friction gear and the driven gear has been increased and the roughness of the driven gear machined surface is changed.
A new friction gear spring and lock nut are available for customer complaints on retailed vehicles. Refer to Inspection Procedure. The spring increases the pressure on the friction gear. Follow the chart below and Inspection Procedure to determine the noise origin. In addition and refer to the workshop manual instructions to replace the friction gear spring(s) on both sides.
NOISE COMPARISON CHART
Use the chart shown to assist in diagnosing the source of noise.
Carbon Knock Noise
Similar to diesel engine noise. Loudest when engine is cold and diminishes as engine reaches normal operating temperature.
HLA Noise
A ticking noise that may occur with a cold or warm engine. Noise may be heard after cold start and also at idle after high speed driving.
Friction Gear Noise
Noise which occurs at normal operating temperature but may also be heard on initial start up. Noise is harmonic at approximately 3 second intervals.
INSPECTION PROCEDURE
1. Verify complaint.
2. Follow the flow chart shown and the comparison chart to identify noise.
^ If the noise is coming from the camshaft friction gear, proceed to Repair Procedure.
^ If the noise is not coming from the camshaft friction gear, refer to the workshop manual for additional information.
REPAIR PROCEDURE
NOTE:
^ The following procedure will allow camshaft friction gear spring and locknut replacement by removing the least amount of components.
^ This procedure DOES NOT replace the current camshaft removal and installation procedure listed in the workshop manual.
^ The differences between the two (2) repairs are outlined below:
1. Cooling system components are not removed. Do Not drain coolant from the vehicle.
2. DO NOT completely remove the intake manifold (from the vehicle). Stand manifold inside engine compartment as shown in Figure 4.
3. Remove the driven side camshaft only. DO NOT remove the timing belt or drive side camshaft.
Repair Instruction
1. Remove fresh air duct, air cleaner, air flow sensor (airflow sensor) and air intake hoses as an assembly.
2. Remove fuel pipe bolts and washers.
3. Remove accelerator cable.
4. Disconnect all high tension leads.
^ Remove leads from supports.
^ Place leads near the distributor.
^ Remove air cleaner support bracket.
5. Remove the harness cover and bolt as shown in Figure 2.
NOTE:
Harness cover must be removed prior to harness removal.
6. Remove four (4) bolts from the timing belt cover. Refer to Figure 3.
7. Remove EGR pipe from Millenia. Refer to Figure 4
NOTE:
If the bolt is rusted-on, cut the EGR pipe to remove.
8. Remove the VRIS solenoid valve bracket bolts.
9. Disconnect the hose from the shutter valve actuator.
10. Remove the intake manifold stay. Refer to Figure 5.
NOTE:
If the EGR solenoid valve bracket is installed on the stay, remove the bolt only.
11. Disconnect the ventilation hoses shown in.
12. Remove the intake manifold.
NOTE:
Stand the manifold in the area made available by removing the air cleaner assembly, airflow meter and the air intake hoses. Refer to Figure 7.
13. Remove the left front bank cylinder head cover.
14. Remove the right rear bank cylinder head cover.
15. Place an alignment mark on the drive side and the driven side cam shafts gear using a scribe. Refer to Figure 8.
16. Remove the driven side camshafts caps, thrust cap and front camshaft cap.
17. Remove the driven side camshaft by rotating it around the drive gear.
18. Hold the camshaft in a vise and remove the locknut, friction gear spring and friction gear.
19. Install the friction gear inside-out and install a modified friction gear spring and lock nut. Tighten to specification: Tightening Torque: 74 - 83 Nm (7.5 - 8.5 Kgfm, 55 - 61 ft-lbs.)
20. Apply new sealant afier cleaning old sealant and residue from surfaces.
21. Install the camshaft so that marks match.
22. Install camshaft caps, thrust caps and front camshaft cap.
23. Tighten bolts in 5 or 6 steps using the sequence below. Refer to Figure 9
CAUTION:
Failure to follow the sequence shown may result in a broken camshaft.
^ Tightening torque: 11.3 - 14.2 NM (115 - 145 Kgf cm, 100-125 in-lb.)
24. Repeat steps 15 through step 23 on other bank.
25. Install remaining components in reverse order of removal.
NOTE:
If the EGR pipe required cutting, install a new pipe.
26. Verify repair.
PARTS INFORMATION
WARRANTY INFORMATION
This information applies to verified customer complaints on vehicles covered under normal warranty. Refer to the SRT microfiche for warranty term information.