Engine - Oil Leak At Timing Chain Tensioner
SI M11 03 11Engine
July 2012
Technical Service
This Service Information bulletin supersedes SI M11 03 11 dated May 2012.
[NEW] designates changes to this revision
SUBJECT
Engine Oil Leak and Timing Chain Tensioner Resealing or Replacement Procedures
MODEL
R55 (Cooper Clubman and Cooper Clubman S) with N12, N14, N16 and N18 engines produced up to 11/2011
R56 (Cooper and Cooper S) with N12, N14, N16 and N18 engine produced up 11/2011
R57 (Cooper and Cooper S Convertible) with N12, N14, N16 and N18 engine produced up to 11/2011
[NEW] R58 (Cooper Coupe and Cooper S Coupe) with N16 and N18 engine produced up 11/2011
[NEW] R59 (Cooper Roadster and Cooper S Roadster) with N16 and N18 engine produced up 11/2011
R60 (Countryman and Countryman S) with N16 and N18 engine produced up 11/2011
SITUATION
^ The customer complains of an engine oil leak from the engine compartment. When diagnosed, the engine oil leak is identified at the timing chain tensioner. In some cases, the timing chain tensioner is only hand-tight.
or
^ The timing chain tensioner is being removed and installed or replaced for the condition described in M11 02 07 "Rattle Noise from Engine".
[NEW] CAUSE
^ The timing chain tensioner seal ring material hardness is too soft, resulting in lost tension during the timing chain tensioner tightening sequence.
or
^ A machining error in the timing chain tensioner sealing surface may interfere with the sealing capabilities of the timing chain tensioner seal ring.
[NEW] PROCEDURE
Vehicles produced from 4/2010 to 9/2010 only:
1. If the engine oil leak is coming from the timing chain tensioner, remove and replace the timing chain tensioner using P/N 11 31 4 609 483. A new and improved timing chain tensioner seal ring will be included with the new timing chain tensioner.
2. If the timing chain tensioner is being removed during any other repairs, be sure to only install the new chain tensioner seal ring P/N 11 31 7 631 972 when completing repairs.
3. Refer to Repair Instruction 11 31 090, "Removing and installing or replacing chain tensioner piston." The chain tensioner piston torque specification is 80Nm.
Vehicles produced from start of production to 4/2010 or vehicles produced from 9/2010 to 11/2011:
1. If the engine oil leak is coming from the timing chain tensioner, remove the timing chain tensioner and replace the seal ring using P/N 11 31 7 631 972. Do not replace the timing chain tensioner.
2. If the timing chain tensioner is being removed during any other repairs, be sure to only install the new chain tensioner seal ring P/N 11 31 7 631 972.
3. Refer to Repair Instruction 11 31 090, "Removing and installing or replacing chain tensioner piston." The chain tensioner piston torque specification is 80Nm.
[NEW] PARTS INFORMATION
WARRANTY INFORMATION