New Generation N62 Engine
Chapter 6 P.3
Course Contents/Background Material
© BMW AG,
Service Training
The design of the fuel tank corresponds to that of the E38. It is
made of plastic and, for safety reasons, is mounted over the rear
axle.
The tank capacity is 88 litres for petrol engines and 85 litres for
diesel engines.
The reserve volume is 10 litres for cars with the N62 engine, and
12 litres for cars with the N73 engine.
The tank system design is very complex due to its safety
features and to minimize its impact on the environment. In
addition, the position of the tank produces two tank halves. This
means that fuel from the left half of the tank must be channelled
into the right half of the tank to enter the fuel pump.
- Filling the tank
There must be no escape of fuel vapours when the tank is being
filled. It must be possible to fill the tank quickly and the fuel
must not foam up.
The fuel tank system must also match the technical classifica-
tions on the fuel filler pumps. The two most important require-
ments for filling up are:
- The flow speed is 15-55 litres per min
- The cut-out pressure is 20-30 hPa
The fuel is prevented from foaming up when the tank is being
filled as the tank filler pipe is located low down on the fuel tank.
An anti-spitback flap (17) is fitted on the fuel tank filler hole. This
flap prevents fuel from splashing back towards the pump nozzle
during refuelling.
