Fuel Tank - RA4700HFM0020X(47-0020)

A. Model 124 

Fig 1: Function Of Fuel Tank (Model 124)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

The fuel tank vent system consist of a central pipe (54) with interruption vessels (54/1) at the ends.

The interruption vessels (54/1) prevent fuel escaping along the vent pipe (64). The vent pipe (64) runs from the central pipe through the vent valve (51) to the activated charcoal filter (52).

Air is supplied to the activated charcoal filter (52) and to the fuel tank (50) from the engine compartment through the cup seal (52/1).

B. Models 129, 140 

Fig 2: Function Of Fuel Tank (Models 129, 140)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

The fuel tank vent system consist of a central pipe (54) with interruption vessels (54/1) at the ends.

The interruption vessels (54/1) prevent fuel escaping along the vent pipe (64). The vent pipe (64) runs from the central pipe through the vent valve (51) to the activated charcoal filter (52).

Model 129 

Air is supplied to the activated charcoal filter (52) and to the fuel tank (50) from the front left side member.

Model 140 

Air is supplied to the activated charcoal filter (52) and to the fuel tank (50) from the rear left wheelhouse.

C. Model 140 with through-loading facility 

Fig 3: Function Of Fuel Tank (Model 140 With Through-Loading Facility)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

On models with the through-loading facility, the fuel tank (50) is lowered in the middle and the expansion tank (55) is located on the outside.

D. Model 202 

Fig 4: Function Of Fuel Tank (Model 202)

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

On models fitted with through-loading facility, the fuel tank (80) is positioned on the frame floor ahead of the rear axle.

The fuel tank (50) is split into two chambers because of the U-shaped recess. The chambers are connected to each other in the top half while the lever senders for the fuel gauge, the suction spray pumps as well as the piping from the left to the right fuel tank chambers are installed in the bottom half.

The splash pot (80/4) is welded into the right hand chamber of the fuel tank and is required as a fuel reserve vessel when cornering and when the fuel level is low. Two fuel feeds, one from each chamber of the tank, and from the fuel filler neck merge in the splash pot (80/4). A strainer (80/6) is installed in the housing of the splash pot and the right suction spray pump at the housing.

The suction spray pump pumps the fuel out of the left-hand and right-hand chambers of the fuel tank into the splash pot. The latter has a nozzle through which the fuel return is accelerated. The return spray from this nozzle flows at high velocity into the pipe running to the splash pot. As a result, it entrains the fuel around the nozzle with it as it flows into the feed pipe and fills the splash pot.

Part of the return quantity flows through the suction spray pump into the left-hand chamber of the tank while the remaining quantity flows through the second suction spray pump. Both pumps fill the splash pot.

Fig 5: Identifying Suction Spray Pump Operation

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

The fuel gauge sender (B4/1), the outlet valve (88) and the suction spray pump (95/1) are attached to the closing plate (89). Each chamber of the fuel tank is provided with a screw plug.

The fuel tank can only be drained through the two outlet valves (88).

Fig 6: Identifying Fuel Gauge Sender, Outlet Valve, Suction Spray Pump And Closing Plate

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.

The expansion tank (39) is installed in the rear right wheel arch. It is used as a collecting vessel for the fuel when cornering and when it heats up.

Fig 7: Identifying Expansion Tank, Vent Pipe To Filer Neck And Vent Pipe For Refueling

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.