Massive fuel leak

[jesuisrelou]

Hello Everyone,

i've encountered a massive fuel leak on my 230.
Fortunately it happened in my own garage but it was quite scary.
First I apologize in advance for my rusty English, french guy writing here.

What happened :
After washing the car, i tried to start it up to go back in its parking slot.
When turning the key, putting the contact on, last position before ignition, i heard an important "liquid noise".
Very similar to an open faucet. I first thought I had not closed the water from the hose i had just use to washe the car.

Unfortunately it was not the case.
When i put the key in its last position, a very important amount of fuel is flowing from the fuel pump area.
It happens only when the pump is supposed to make its little noise before starting up.

There is no leak when the car is sitting untouched.


Given that the fuel pours only when the pump is on, would it be correct to assume that the issue is probably a faulty hose or clamp after the pump ?

Or could this behaviour be caused by a faulty pump ?

I've ordered a hydraulic jack and jack stands, hopefully I will find the culprit when lifting the car.

Thank you very much in advance for your valuable advices.


EDIT : here is a picture of my beauty

[stickandrudderman]

Probably just a split fuel hose. It's a quick and easy fix but since that one has failed it follows that all others are likely perished and you should consider changing them all.

[ejboyd5]

The British idiom featuring the word "perished" is marvelously appropriate.

[Figoulu]

Hello from France as well

The fuel lines are quiet simple on this car

The connections are rather next to the electric pump / fuel tank area to the rear of the car, or to the filter and its suroundings, inclunding the mechanical fuel injection pump
As mentioned before it's wether a worn hose or a clamp that is not enough fastened

The 2 lines that goes underneath the car are made of metal, I guess it's not about that

[jesuisrelou]

Thank you for your answers !
As you guessed, it was clamp that went loose, I replaced it.

But the fuel lines are all dry (not to say almost rotten)
I'm gonna order new ones i replace them all.
It seems quite easy for the ones after the fuel pump, but for the ones between the pump and the tank i might need to go to a shop.

[Pawel66]

The one tank-pump you would have to undo on the pump side and put into some container to drain the tank.

If I may, from an amateur perspective: it may be a chance to do it in a complex way maybe. You could, just food for thought:

- you could undo and clean the filter in the fuel tank
- you could undo and clean the filter in the fuel pump (and check if it is there)
- i think it is a good idea to install additional filter between the tank and the pump
- replace all rubber in the rear
- check the condition of flexible hoses in the front and replace if need be
- change the main fuel filter
- change all the clamps

Again, just a thought - it is fuel.

I bought al the rubber from mercedes dealers. Main filter and tank filter as well.

[boterinse9]

Helle   fuel leak. I had the sam when pulling out of my garage, long story short ruptured fuel line in the bend of the hose this was my 3rd or 4th time  those German hoses are lousy the material deteriorates  so I cut the metal end with nut off and bought a  few feet of quality hose and attatched to the curved nipple.  problem solved and made a spare to keep in the trunk.. bonjour  ami...

[stickandrudderman]

those German hoses are lousy the material deteriorates 

Yes, they only last a few lousy decades! 

[MarkCan]

Since your hose rapture, imagine the contamination it caused before it happened. Be kind to your IP.
Plan for it and redo the whole fuel delivery system. It’s not that complicated and inexpensive to boot. I did the front end on the 230sl  and the complete system on the 300SEL. Provided you buy good quality fuel hose you will have trouble free, reliable system for years to come.

[boterinse9]

My fuel lines developed pinhole leaks and and one looked deteriorated.  so I keep an eye on it  also installed a pre pump filter as per  Kent Bergsma. I do what I can.    A Merry Christmas to you and yours..

[MarkCan]

My fuel lines developed pinhole leaks and and one looked deteriorated.

let’s smile and decode that secret message.
If that fuel hose could only speak, I guarantee you it would say;
Please help me rest, take me out of here, I’m falling apart. I’ve sent you a message by opening just a small pinhole but I really don’t know how much longer I can hold it together.

Hey, I’m watching my childhood hero Donald Duck, can you tell?
Merry Christmas everyone.

[boterinse9]

Was always smelling gas but not seeing it. it evaporated too fast  till I crawled under it  and waited  discovered it.  done....

[boterinse9]

Agree  the first on car lasted that long  But I had two  more since from dealer and they developed  pinholes and when scratching the spot the came apart Took the fitting of and made my own hose looks pretty strong and durable. so we shall keep an eye on it. Also found out not to get any fuel filters with any rubber tabs. on them had one totally disintegrate and clogged the filter in one year..

[boterinse9]

Had that happen to me in the middle of the bridge in st Charles ill on Sunday got towed home after removing filters totally black and the rubber parts were disintegrated  nomo rubber parts lesson learned