64 12 500 Removing and installing or replacing complete heater
M57 only:
Remove air guide from fuel cooler.
Loosen screws (1).
Detach fuel cooler (3) in direction of arrow from guide (2) and place to one side.
All:
Disconnect plug connections (1) to (3).
To avoid damage during installation, it is absolutely essential to adhere to the following contacting sequence for the plug connections:
- Plug connection (1)
- Plug connection (2)
- Plug connection (3)
Unfasten hose clip (1).
Detach intake hose (3) in direction of arrow from heater (2).
Release screws (4).
Danger of scalding!
Only perform this work after engine has cooled down.
Detach fuel line (1) from heater (5).
Release hose clamp (3).
Detach water hose (2) from heater (5).
M57 only:
Release screw (4) and remove retaining fixture with centering for fuel cooler.
Installation
Make sure retaining fixture with centering for fuel cooler is correctly seated.
M54, M62 only:
Release screw (4).
All:
Detach exhaust hose (6) in direction of arrow from heater (5).
Lift heater (5) upwards.
Unfasten hose clip (2).
Detach water hose (1).
Lift out heater.
Installation
Replace gasket (3).
Make sure exhaust hose (4) is correctly seated on flange of heater (5).
Fill and vent cooling system. See VENTING COOLING SYSTEM AND CHECKING FOR LEAKS (M54/M56) .