Repair notes for cylinder head or engine replacement

Problem 

After replacing the cylinder head, a loud rattling noise occurs in the area of the cylinder head or cylinder head cover after starting the engine. One or more roller cam followers can pop out.

Cause 

The new part cylinder head does not contain any engine oil. The oil supply to the valve clearance compensating elements on the exhaust side and in the area of the exhaust valve stems is not optimal at the first engine start.

Measures 

Observe the sign in the engine compartment! Only pour in approved motor oil with the correct SAE viscosity classification.

Before installing the cylinder head cover, the valve stems of all exhaust valves must be moistened with engine oil.

Before the first engine start, the engine only needs to be turned with the starter (without combustion) for a few seconds. The maximum permissible uninterrupted operating period must not be exceeded.

Maximum permissible uninterrupted starter operating period: 15 seconds

To guarantee this, the electrical connections of all injectors must be disconnected. Alternatively, the wiring harness for injection and ignition must be unplugged from the Digital Motor Electronics (DME), but without removing ignition coils and spark plugs. For additional information, see: CHECKING ALL CYLINDERS FOR LOSS OF PRESSURE (B48 AND B46 ENGINE) (COOPER S AND JOHN COOPER WORKS) .

Turning the engine with the starter (without combustion) ensures that the valve train has a sufficient oil supply to start the engine regularly afterwards.

Then reconnect the injectors or the wiring harness for injection and ignition to the Digital Motor Electronics (DME).

Delete the fault memory.

Start engine.