R129 SL500 Hydraulic Fluid Drain

[1001ab]

I'm looking for help with the best way, either the official procedure or the best method with the benefit of experience, to drain the hydraulic fluid on an R129 SL500.
It looks dirty compared to the fresh fluid and I have a lot of fresh fluid sitting from an S124 I bought a few years ago that came with seven litres in the boot.

Thanks in advance.

 

[Borys]

I did this over weekend on my cl500 Took an empty 1ltr bottle, attached pipe to it Every corner has a 8mm drain plug, similar like brakes Heat up the oil, raising car up and down few times Then on every corner - 1 ltr out and 1 ltr in with engine runing Just make sure pump will not run dry Also be careful oil can get quite hot Similar principal as with brake fluid

On pic oil which came out of my system :-0

 

[1001ab]

Every corner has a 8mm drain plug, similar like brakes

Nice one, thanks.

 

[BTB 500]

I don't know the answer to your query but I guess you mean the roof hydraulics (unless your car has ADS)? Borys is talking about suspension though.

 

[1001ab]

I don't know the answer to your query but I guess you mean the roof hydraulics (unless your car has ADS)? Borys is talking about suspension though.

Yeah, I had a look under the car last night and realised.

I'm talking about the underbonnet reservoir which I understand is for the roof, I was looking to drain it to get fresh, known good fluid in.
I'm worried about bleeding too, if that's an issue.

Apologies if I was unclear.

 

[219]

The reservoir for the roof is under the spare wheel in the boot .

Out of curiosity , do the roof hydraulics use the same ZHM hydraulic oil as the estate car SLS system ?

 

[tommyboy40]

the reservoir for the roof is under the spare in the boot and needs specific MB type fluid

 

[1001ab]

The reservoir for the roof is under the spare wheel in the boot .

Out of curiosity , do the roof hydraulics use the same ZHM hydraulic oil as the estate car SLS system ?

I asked at the dealer parts desk, they said yes.

the reservoir for the roof is under the spare in the boot and needs specific MB type fluid

So if I've got a reservoir under the bonnet then I have SLS AND another reservoir for the roof hydraulics that I haven't yet looked at?

 

[BTB 500]

If you have ADS there will be a rocker switch on the centre console with a picture of a shock absorber on it (standard/sport).

 

[tommyboy40]

ADS was rare on 500's and you'll know if you have it by the control at the light switch

 

[Borys]

Ups

 

[BTB 500]

ADS was rare on 500's and you'll know if you have it by the control at the light switch

AFAIK only ADS II cars have that - don't know what age the OP's is. That's why I mentioned the switch on the centre console, which both types have.

 

[moakesr]

AFAIK only ADS II cars have that - don't know what age the OP's is. That's why I mentioned the switch on the centre console, which both types have.

My 1991 500SL with ADS1 has the height control switch at the side of the light switch.

 

[1001ab]

My car is Jan '91 registered, so probably a '90 build and has both the 'shock absorber' button on the lower centre console and a switch next to the light switch, as described above.

The fluid is manky but everything seems to work okay so I'm less confident about changing it.

My boot is so full of stuff that I haven't yet checked the reservoir for the roof, is there a drain for that?