mattjd247

Hi there

I drive an early W216 CL500 (we call her Brunnhilde).

About 4 weeks ago I got the dreaded humming sound at below 2000rpm. £2k later at an MB main dealer, and she has had a new tandem pump and a hydraulic system flush. Hurrah!!

Fast forward 2/3 weeks. Yesterday, after 10 minutes of driving I get a yellow warning on the instrument cluster: 'ABC Malfunction'. Oh dear.

When I get home, I have a little look around and notice a puddle on the floor by the front left wheel. I had noticed this about a week ago but (for my sins) thought nothing of it (we park in a basement carpark and sometimes get little puddles from run-offs etc). I touch the fluid and it is slightly greasy.

This morning, when the engine is cool and off, I check the hydraulic fluid level. It is 1 inch off the bottom of the dip-stick. I also wipe the fluid off the floor - it has a pale green colour.

I deduce I have a hydraulic fluid leak somewhere.

Question: is it more likely that:

A) something was not reconnected properly/tightly when the tandem pump was fitted, resulting in a slow leak; or

B) I have a leaking hydraulic hose somewhere, unrelated to the tandem pump replacement.

My feeling is A), but only because of the proximity in time to the tandem pump replacement.

Many thanks (and sorry for the long post!!).

Matt

dbldpr

I would go with A also. If there was no leak before and there is now they did something wrong.

mattjd247

Thanks for the reply- I hope we are both right! Sadly, it will be a long time until I find out- the MB dealer I used is closed because of Covid-19.

I'm mainly sad I won't get to enjoy the car for a little while!

dbldpr

In Illinois the car sales are by appointment but service is open. Sorry you have to wait.

DMWelk

Unfortunate for you, In my area (Washington) sales dept. are open by appt. and service dept are open and if your not comfortable bringing your car to them they will come and pick it up and return it when the service is finished.

chassis

Welcome! Please post a photo of the CL500.

mattjd247

Here she is! I have changed the wheels since this was taken.

mattjd247

UPDATE

It turns out that the small hose between the hydraulic fluid reservoir and the tandem pump (which hose apparently carries the hydraulic fluid at its highest pressure) had degraded and was leaking. Fortunately this is a cheap and quick repair!