W212 coolant and power steering

[Porto]

Hi,
2013 w212 2.2 diesel CDI estate.
Yesterday I noticed the steering was sometimes a bit heavy at low speeds, then the low coolant light came on. Today I topped up the coolant a little bit and checked the power steering pump reservoir, which was OK. I took the car for a low speed test run for only a mile or so then when I got out of the car the driveway was covered in coolant which was leaking from under the car.
- Is there a possible link between coolant and the power steering?
- What are the likely causes for such a sudden & drastic loss of fluid?
- Ideas for a good workshop manual for the W212?
Thanks
P

 

[steveq]

It is unlikely that there is a link unless it is related to the serpentine belt that drives both the coolant pump and the power steering pump.
I suggest that you take off the engine cover, the air intake pipe and the cover from the front of the engine. That will expose the serpentine belt and the coolant pump.
Check the condition of the belt. That also drives the alternator so if it failed the dashboard would be lit up like a Christmas tree.
The coolant pump can leak but it is unlikely to suddenly go from no leaks to suddenly gushing out.

The online manuals available tend to be American and so don't cover diesel models.
It is possible to get copies of the MB WIS workshop manuals.
They won't help much in the diagnosis though.

 

[steveq]

Does the temp gauge go up to the normal position (85 - 90 degC)?

Did you overfill the coolant reservoir?
Just fill it so that the coolant is up to the top of the white part. Don't fill it into the dark top part of the reservoir as there has to be room for expansion.

 

[Gazwould]

It's an OM651 guys , they don't like the taste of coolant..

 

[Porto]

It is unlikely that there is a link unless it is related to the serpentine belt that drives both the coolant pump and the power steering pump.
I suggest that you take off the engine cover, the air intake pipe and the cover from the front of the engine. That will expose the serpentine belt and the coolant pump.
Check the condition of the belt. That also drives the alternator so if it failed the dashboard would be lit up like a Christmas tree.
The coolant pump can leak but it is unlikely to suddenly go from no leaks to suddenly gushing out.

The online manuals available tend to be American and so don't cover diesel models.
It is possible to get copies of the MB WIS workshop manuals.
They won't help much in the diagnosis though.

Thanks for the reply. I have checked the serpentine belt and it seems tensioned & in good condition. I had to reposition the car in the driveway and the steering is so heavy, & the coolant is still pouring out from somewhere. In the absence of anything else I've ordered the W204 C series Haynes manual as I think that also has the OM651 engine. Suggestions please on other coolant weak points for me to start with first.
Cheers
P.

 

[Gazwould]

Water pump and fuel filter housing coolant inlet / outlet .

Both now redesigned as originals are guaranteed to leak .

 

[Porto]

Water pump and fuel filter housing coolant inlet / outlet .

Both now redesigned as originals are guaranteed to leak .

Thanks, I'll check them.
Cheers
P.