GF47.10-P-3004A On-board refueling vapor recovery function 12.5.98

MODEL  215 up to 31.8.00 with ENGINE 137, 113 with CODE (494a) USA version


P47.10-2009-79

Shown on Model 210 sedan
45 Filler neck (connection for collecting fuel vapors when refueling)
45/1 Flap
45/2 Float with flap
45/3 Corrugated tube
45/4 Pressure relief valve (in top insert integrated at corrugated tube, release pressure approx. 60 - 90 mbar)
75 Fuel tank
77 Activated charcoal canister
  77/1 Pressure relief valve
(release pressure approx. 30 - 40 mbar)

82 Pressure relief valve in ORVR vent line
(release pressure approx. 60 - 90 mbar)

Y58/1 Purge control valve
Y58/4 Activated charcoal canister shutoff valve
A Nozzle, extraction through metal tube
B Nozzle, extraction through rubber boot (overflow not recognizable)
  a ORVR vent line (from filler neck to activated charcoal canister)
b Hose line to pressure relief valve
c Fuel overflow line to atmosphere
d to engine
e Fuel overflow line to atmosphere (to tank recess)
f Fuel tank air admission line

Task
The legislator requires, that the refueling gases in the vehicle are collected (ORVR = Onboard Refueling Vapor Recovery).
Separate fuel and refueling gases to prevent fuel from flowing into the activated charcoal canister due to inappropriate refueling or a defective nozzle.
 


Ending refueling when the refueling nozzle switches off and the fuel tank is full! On no account overfilling fuel tank as a result of refueling nozzle being switched on several times.

Function
The fuel vapors are recovered at the filler neck (45) and passed along a ventilation hose (a) to the activated charcoal canister.
An insert inserted in the filler neck prevents, that when refueling fuel flows to the activated charcoal canister.To do this

 
the fuel vapors in the filler neck are diverted several times in order to separate the gases from the fuel.
The connection to the activated charcoal canister is shut off by a flap (45/1) when driving. It is opened by the gasoline pump nozzle when refueling.

Additional measures if fuel tank is overfilled
If the fuel tank is full, the float (45/2) closes with flap the filler neck below. This ensures that the refueling nozzle shuts off more rapidly and overfilling is largely prevented.
A too high level of fuel in the filler neck presses open the pressure relief valve (45/4). Fuel flows to atmosphere at the nozzle. End refueling!
On nozzles fitted with rubber boot (B) this overflowing is no longer recognizable.
 
A too high pressure in the ORVR vent line (a) acts on the diaphragm in the pressure relief valve (82). If the diaphragm lifts off because of excessively high pressure, the pressure is released at the fuel tank recess (e) and below the wheelhouse to atmosphere (c). End refueling!
If the pressure is too high in the activated charcoal canister (77), the pressure relief valve (77/1) opens. The pressure is reduced through the activated charcoal canister shutoff valve (Y58/4) to atmosphere (c).

  Fuel filler neck with closing cover location/task/design/function   GF47.10-P-3003B
  Refueling vapors pressure relief valve, location/task/design/function   GF47.31-P-3100A
  Activated charcoal canister location/task/design/function in the case of ORVR with integrated pressure relief valve; volume approx. 2.7 l GF47.30-P-3102F
  Activated charcoal canister shutoff valve location/task/design/function   GF47.30-P-4033L
  Purge control valve, location/task/design/function   GF47.30-P-4030L
  Evaporative emission control system function   GF47.30-P-3013L
  On-board refueling vapor recovery function as of 9/00 GF47.10-P-3004B