MX-6 LS V6-2.5L DOHC (1997)
Camshaft Oil Seal: All Technical Service Bulletins
Engine - Slight Oil Leak/Metallic Tapping Noise
B005/98
CAMSHAFT 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.
