Warnings And Cautions - BMW 5251 Service Manual

Warnings and cautions
O b s e ~ e the following warnings and cautions when worlting
on the cooling system.
WARNING
-
.
At normal operating temperature the cooling system is
pressurized. Allow the system to cool as long as possible
before opening (a minimum of one hour), then release the
cap slowly to allow safe release ofpressure.
a
Releasing the coolant system pressure lowers the cool-
ant boilingpoint and the coolant may boil suddenly. Use
1
heavy and wear eye and face protection to
guard against scalding.
Use extreme care when draining and disposing of en-
gine coolant. Coolant is poisonous and lethal to hu-
mans andpets. Pets are attracted to coolant because
of its sweet smell and taste. Seek medical attention im-
mediately if coolant is ingested.
C A U T I O G
Avoid adding cold water to the coolant while the engine is
hot or overheated. If it is necessary to add coolant to a hol
system, do so only with the engine running and coolanl
pump turning.
To avoid excess silicate gel precipitation in the cooling
system and loss of cooling capacity, use BMW coolant
or equivalent low silicate antifreeze.
a
If oil enters the cooling system, the radiator, expansion
tank and heating circuit must be flushed with cleaning
agent. BMW recommends removal of the radiator and
expansion tank to flush.
When worlcing on the cooling system, cover the alter-
nator to protect it against coolant drips.
Prior to disconnecting the battery, read the battery dis-
connection cautions given in 001 General Warnings
and Cautions.
Begin the diagnosis of cooling system problems with a thor-
ough visual inspection. If no visual faults are found, it is rec-
ommend that the engine control module (ECM) fault memory
be checked for stored diagnostic trouble codes (DTCs) using
BMW scan tool DlSplus or equivalent.