R230 ABC oil leak under front left (NS on RHD)

[Marcus88]

Hello, I have a 2005 R230 SL500. There is a pool of ABC fluid under the front left behind the wheel arch / sill area. From what I have researched, the Pulsation dampener, Pressure Supply Valve Unit and ABC pressure sensor are in that area. I have no warnings on the dash.

I have peered underneath and the fluid seems to be running down from the undercover.

Any advice on how to remove the cover and where to start looking would be greatly appreciated.

 

[ajlsl600]

Front left ie p/s. Just behind wheel? There's a few pipe connections in there I had a weeping pipe. £100 fix. Wheel off liner out. Less than hr No big issue. Also in there horn/alarm that beeps when you lock car.

 

[John Laidlaw]

Welcome Marcus
This will help locate the various components
However I would say dropped fluid is never a good thing, warnings might not be there yet, but lack of fluid in the ABC can escalate failure of the pump especially very quickly, something you don’t want!
Most of these parts are not easily accessible (radiator out to access the pump for instance).I think what you’re looking for might require removal of the NS front wheel liner from memory? I would suggest not running the car until you can get it looked at by someone who knows ABC well. Where are you located ?

 

[Marcus88]

Hi, thanks. Yes, I will not run the car until its fixed. I have take the front wheel off and the liner, here are some pictures of the area. Located Worcester, UK.

 

[LostKiwi]

I'm not seeing any fluid leak there?

 

[Marcus88]

I'm not seeing any fluid leak there?

Right, maybe is leaking from the back where the Pulsation Dampener fits, it leaking and running along the cover ...see pciture attached

 

[ajlsl600]

Is switch leaking, or above, behind? Clean area well. Have someone opp the ride height switch in car. Should see something..

 

[ajlsl600]

Pic 3 of 7 on mine leaking from swaged joint on pipe in lower left of picture.

 

[Marcus88]

Is switch leaking, or above, behind? Clean area well. Have someone opp the ride height switch in car. Should see something..

Sorry which switch ? I will go and clean the area, thanks for your help

 

[ajlsl600]

In Pic 1 there is a switch./sensor, Of some kind, pressure?
Sometimes these leak between casing and plastic. If so only long term solution, replace. Clean whole area run, observe given system pressures you should see something, try a clean white cloth or paper under that area to pin point. But do cycle the height switch in car

 

[Marcus88]

In Pic 1 there is a switch./sensor, Of some kind, pressure?
Sometimes these leak between casing and plastic. If so only long term solution, replace. Clean whole area run, observe given system pressures you should see something, try a clean white cloth or paper under that area to pin point. But do cycle the height switch in car

I have found the leak. See picture. The bolt on the banjo fitting was quite loose, I tightened it up but it still leaks. So hopefully, I just need a new O-rings /washers.

Does anyone know what size O-ring / washer? 2pcs right?

Many thanks for all the help.

 

[LostKiwi]

What's the green stuff squeezing out from under the sealing washer?

 

[Marcus88]

What's the green stuff squeezing out from under the sealing washer?

I noticed that too, looks like a previous bodge job. If I undo and remove the banjo bolt, likely a lot of fluid will come out right, although if its been leaking the pressure shouldn;t be bad. do I have to some how bleed it once I put the new O rings in? Thanks

 

[LostKiwi]

System should self bleed. Ideally you'd use Star to run a rodeo test to force the air out but cycling through the heights several times should suffice.
Be careful undoing the banjo - there may be a lot of hydraulic pressure present.

 

[Marcus88]

System should self bleed. Ideally you'd use Star to run a rodeo test to force the air out but cycling through the heights several times should suffice.
Be careful undoing the banjo - there may be a lot of hydraulic pressure present.

Ok thanks for your advice, I will leave it overnight which should reduce the pressure a bit due to the leak. Any idea what size O-rings they are? The Head of the banjo bolt is 19mm, so I guess M12 or M14. Cheers

 

[LostKiwi]

They should be copper washers not o rings. An o ring would be unlikely to stand the pressure (200 bar = 2950psi approximately).

Sorry don't know the size.

 

[John Laidlaw]

Not sure what the washer size is but for the sake of a few quid it might be worth contacting MB Grangemouth 01324 686002 for the correct part ?

 

[John Laidlaw]

I think they are dowty seals if I remember correctly

 

[Marcus88]

Not sure what the washer size is but for the sake of a few quid it might be worth contacting MB Grangemouth 01324 686002 for the correct part ?

Many thanks for your help

 

[ajlsl600]

Maybe someone put copper washers and what we see in photo is corrosion of same?
As long as Benz marketing can supply the correct parts/seal washers. Without having to buy valve Ias well?? I would go for that. High press and a pain if you have to do it again