5 Series E34 525ix (M50) SAL
MK-21/Seyfried
Baugruppe/Group: 11
11 10 98 (367)
weltweit
all countries
10/1998
Rattling noises from the area of the valve timing gear
M42, M50, M52, M60, M62, S50U, S52
Situation:
The most common reason for replacing the hydraulic valve clearance compensating
elements (HVA elements) is rattling noises in the area of the valve timing gear immediately
after a cold start.
Comprehensive investigations on exchanged HVA elements show no signs of irregularities.
These noises can be traced back to the higher viscosity of the cold engine oil.
For a brief moment, insufficient oil reaches the high pressure chamber of the HVA element
via the high pressure valve. This results in clearance between the HVA element and the
cams, which then causes the "rattling noise" which may be the subject of a complaint.
Rattling noises may also occur in the area of the valve timing gear if HVA elements
become compressible due to ingress of air. This occurs in isolated cases after frequent
short journeys in which the engine does not become properly warm.
The above conditions are caused by technical principles and have no damaging effect on
the service life of the engine.
Similarly, air being drawn in by the oil pump, e.g. after extreme cornering or if the engine oil
level is at minimum, can also be responsible for such rattling noises.
To allow faster diagnosis, enclosures 1-4 describe different fault patterns. These 4
enclosures apply to all spark ignition engines with HVA bucket tappets.
Furthermore, enclosures 5 and 6 describe two fault patterns which in the past have been
incorrectly diagnosed as causing rattling noises through compressible HVA elements:
-
E36/M52: Ticking noise from the tank-ventilation valve
-
E34, E36/M50, M52: Rustling noise from the valve timing gear/VANOS
Affected
vehicles:
E30, E36/M42
E34, E36/M50
E36, E38, E39, E46/M52
E31, E32, E34, E38/M60
E31, E38, E39/M62
E36/S50U
E36/S52
Procedure:
The actions described in this Service Information bulletin are only to be carried out in case
of customer complaint .
Enclosures 1 to 6 are not only of relevance to the workshop , but also to the Service
reception .
Competent questioning of the customer in the service reception should give a precise
description of the fault pattern, which can then be passed on to the workshop (quote from
customer).
In summary, the following fault patterns must be differentiated:
Enclosure 1 - HVA rattling after a cold start
Enclosure 2 - HVA rattling after frequent short journeys
Enclosure 3 - HVA rattling after extreme cornering
SI Rattling noises from the area of the valve timing gear M42, M50, M52, M60, M62,
BMW AG - TIS
21.01.2013 19:39
Issue status (12/2007) Valid only until next DVD is issued
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