Dreaded ABC malfunction - but with a twist

[PHAB]

Hi all, currently getting to grips with a 2003 SL55, one previous owner & 58,000 miles after a lot of R129s. Have STAR etc so know what im getting into and a decent understanding of the weaknesses of the R230. Specifically for the ABC so far I have changed the Tandem pump (pressure during Rodeo not to spec), and done full fluid flush and filter change. The car never sinks on any corner even after months of non use and until today it has never missed a beat - aside from usual R230 erm....novelties (rear boot lock, rear windscreen seal, rocker covers weeping, creaking roof, SBC replacement etc etc etc).

Today pulling onto a slip road I got the deaded ABC Failure, drive carefully. Pulled in at a layby and switched off and straight on....all warning lights off. Gingerly drove home. On opening the bonnet it seems that there has been a ABC fluid leak from the reservoir but nowhere else, everywhere else is bone dry. Its as if the pressure has shot up and its popped the dip stick cap and shot approx 100ml of fluid in the local area - very odd!

Please let me know if this rings any bells with anyone. My STAR kit is about 45 mins away so I will top up the reservoir and drive carefully back - the pump sounds healthy, the car is going up and down as it should etc and I cannot see a leak from anywhere. My suspicion is a failed pulsation damper - as there was a very faint vibration through the steering wheel at low revs before this happened - still there.

Thank you in advance for any thoughts.

 

[Will]

No expert on ABC but usually on hydraulic systems like this the pressure accumulators split and the pressurised nitrogen forces the fluid out, I guess the pulsation damper must act in a similar way.

You may find this thread useful:

SL55 spat out its ABC fluid today | Wheels, Tyres, Brakes & Suspension

I got an ABC warning workshop visit today. When I got home I opened the bonnet to find oil sprayed on the inside from the reservoir. I understand this is likely to be an accumulator and I think it’s the rear. I’ve decided to replace all the accumulators. what side of the car are they on and how...

forums.mbclub.co.uk

HTH

 

[PHAB]

Pulsation damper removed the morning...accumulator shot to bits and definitely perforated. Going to replace other two as well and do a fluid flush. Thanks v much for pointers Will.