What is this and why is it leaking?

[kbahus]

Hi guys, total 250SL new guy here. This car has been sitting for quite a long time and when moved had a puddle that was quite large under it. I initially thought it was diff fluid but when moved to the garage I was able to look and see that the item leaving a puddle looks like a mechanical fuel pump and it is still leaking fluid. It has a oil consistency but smells a bit like fuel. What am I dealing with here? Any help would be greatly appreciated.

[scoot]

The pictures seems strange - the 113 cars (250 SL) have an electric fuel pump that is mounted as shown in your photo.  Mine doesn't have a cover on it, it looks like yours does.  If you turn the key to the "on" position, you should hear the pump operate and possibly start dripping more.  You might want to start with reading the Forum's technical manaul on the fuel system: http://www.sl113.org/wiki/Fuel/Start

There is no reason that you would have a mechanical fuel pump, and no reason for there to be oil as part of the picture unless oil is leaking from the differential and landing somehow on the fuel pump, but I can't really imagine that to be the case.

[Flim]

The technical manual will be a great place for you to start to find out the root of the problem.
I have a 250SL (early, chassis number 000238) and it has the same fuel pump cover protecting it. I had a presumably similar problem last September: turned out to be the fuel hose which runs from the tank to the pump was perished....
Good luck

[jeffc280sl]

You are looking at the cover/shield of the electric fuel pump.  It is secured by two bolts which go up into the trunk floor.  Take the bolts off and remove the cover to see what is most likely and hopefully a brittle and cracked fuel hose.

[ja17]

Hello,

If you are lucky, it is just a rubber fuel line.  They dry rot and deteriorate with age.  Change all rubber fuel lines under there while your at it.

If your not so lucky it is the electric fuel  pump which is leaking.  Still a good idea to replace the rubber fuel lines..

[RickM]

I agree with the above posts.
When I purchased my 280 I had to replace the fuel pump lines in order to get the car home.

I assume a '71 280 should have the same cover...?

[scoot]

I assume a '71 280 should have the same cover...?

The covers are often missing.  Particularly on cars that originally had the early longer pump and had that replaced with the later shorter pump.

[hands_aus]

FYI
here is an article in the Tech manual you might find interesting.
http://www.sl113.org/wiki/Fuel/FuelPumpRebuildEarly