I got a face full of fuel when doing a fuel pump change for a customer on a 1980s mercedes 380 se. I have not seen a case where the fuel comming into the supply line is under some kind of pressure. I removed the pump to the left of the right rear tire and as soon as I removed it, the fuel flowed at a high rate comming from the supply line. I got partially soaked and was really supprised at the flow rate. I did not see the tank so does this line come from the bottom of the fuel tank? Almost all fuel pumps the line comes from the top of the fuel tank. When asking the customer if the ignition key was off, he said it was.

Secondly, the fuel pump the owner provided me was of the wrong diameter. After putting it in its braket, the pump was to small. Braket could not hold onto it. We went to the parts store, lordco, and there was three different pumps for this vehicle. So we exchanged it for the one with the rubber sleave. Started up the car and everything worked out for the customer.

So, I dont want to experiance this shower of fuel again. The pump supply line looks like it is a hard plastic with rubber coating on it so dont want to pinch it to remove the next pump. What can be done to stop the fuel flow when doing the next pump change?

 

All tankes I have worked on the line comes out the top. In the case of Mercedes, its out the bottom? or other?

Other then draining the tank which is what I suspect a Mercedes shop would do there is no other choice correct? Having fuel spray is very hazardous should static be present in the area.

 

yeah, one of my pumps sprung a leak. I just let it leak into a large drip pan like device until empty (took only three hours from 1/4th tank). Then repaired pump at leasure with little gas spilled. Unfortunately couldnt reuse gas as the drip pan was dirty and on loan from the local EPA (long story). After replacement, put new gas into the tank and took a few seconds for the fuel to get to the engine and start but good as new. It's under pressure without key to facilitate quick starting. The check valve on the fuel pumps also play a role.

I like the way the fuel system set up in the S-Class is. Easy. You dont have to drop the tank to get to it as getting the tank out of that thing is a pita. Just clamp off lines to avoid spilling fuels and go to work with the tools.

 

On my S-class '80 280SE I have pinched it with C-clamp before pump removal.
But aftermarket pump was so noisy that in two weeks I replaced it with OEM Bosch.
Pump was louder then my engine plus hissing exhaust together, it was not my Mercedes any more, pump was made or sold by Carquest auto parts. Junk streight from mfg.!