R129 buying advice

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5sp box is a slightly more spirited to drive with the extra ratio and electronic control, and the Motronic gets rid of the LH-Jetro's distributors.

Timing chain I would ignore until it actually needs doing - you'll get plenty of warning.
Leads will probably be tired if original. Caps and rotors do as required.
Springs will be fine unless you want to lower/uprate, but new shocks and bushes will make it feel fresh and taut. Not cheap though.

I presume by flexi-disc you mean driveshaft donuts? Again, do them as and when needed.
My 91' 500 SL 's ignition was playing up....... When I first bought the car in 2006 I was assured and saw bills from an MB specialist stating rotors , leads , barrel etc had been replaced and something to do with the distributor (I'm not a mechanic) as the 500's had a frequent problem with them. My 500 started first time everytime ( without any throttle of course) until a couple of days before I sold it for an audi convertible 1.8T sport ( had to carry 4 new ignition coils around with me for that sludge prone engine).
During that last couple of days with the 500SL the engine did start but only after the application of the throttle. And ran fine.
As for the SL320 I had ( 1994) The nearside wing ( no known previous damage) was starting to rust. Wings are cheap enough on ebay. The 320 every now and again also needed a little throttle to fire up. Ran fine though. Electrics is the key I think.
Although my SL350 3.7 is more a 'sports' car I do miss the utterly solid feel and drive of the 91 500 SL. MB specialist mechanics in Leeds and Wakefield all concurred that the exhaust systems seem to be pretty bullit proof.
The W126 needs a bit of throttle to get started when its cold, havent had the time to dig into that problem....

On the M116/M117 engine you needed to be pretty sharp about replacing the timing chain rails as over time they would get brittle and could break. causing the chain to jump resulting in serious wallet injuries.

If the doughnut/flex went on the W126 it could tear up the transmission tunnel :(

Quoting Grober from 2010

"The changeover from KE Jetronic to LH Jetronic occured from October 1992. This co-incided with a slight reduction in power from 326 to 320 bhp Best dated by simultaneous introduction of the V12 600SL model."
I think if the donut goes on any car it's not a good thing. But you get plenty of warning, and regular inspection will tell you when it needs doing. I've only ever known spontaneous explosion through wilful neglect.

The M119 doesn't suffer the same issues - chain replacement is rare. There's a guide at the top of the engine that sometimes needs doing but IIRC again you get warning, it's a very cheap part and you only have to lift the cam cover to access.
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Hi All,

So I managed to view a couple of R129s.

I saw a facelift which I didnt get a warm feeling from the seller and the body had rust in all the hotspots. So thats been crossed off the list

The second one i had a better feeling about it was a 95 model, however I have a few further questions after having a gander at these.

I noticed that it had a slightly hard shift from 1st to 2nd and smooth shifts on the other gears. It dindt look like had the ATF changed and it has done around 95K.

What would be the cost of a ATF fluid/filter change on one of these?

The aircon compressor kicked in but did not really blow cold, apart form the re gas that everyone claims and common faults that this could be?

It believe it needs a new soft top as its quite worn and has small splits in the plastic. Its original as it has the merc logos on the plastic.
The owner claims that it is watertight as he had it pressure washed and it didnt leak but surely splits would let in water?

What is the cost of a good new soft top and how much does the cost vary between a good one and not so good?

There is a squeak that comes from the left rear wheel, what might this be shocks/ bushes/arb?

It is running 17" AMG alloys which are larger width at the rear Im guessing these had been fitted at some point in its life as the spare is the standard 8 hole jobbie.

It also will need a new exhaust in the near future as there is plenty of corrosion on it, MB price £800? and a SS replacement less?

My major concern is that the airbag light does not illuminate which is an MOT fail. Im guessing the bulb has been removed before the chap bought the car(he has had it for 9 years). What are the likely things that could cause an airbag fault?

Also the foam from the bonnet has mostly peeled of, is this around £60 in materials?

Overall it does seem like a fairly honest car though, what would be a fair asking price given these issues?

Cheers fro your help

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If the compressor kicks, there's still some gas but it's likely that the condenser is looking pretty ropey and allowing gas to escape.

Squeaking is probably bushes, but without seeing/hearing it's hard to be 100% accurate.

AMG alloys could have been fitted as new, spare would still be 8 hole as it only replaces the main 4.

Exhaust may look bad on the outside, but they're double skinned and pretty bombproof. Plenty of replacement options depending on required budget.

Airbag light - could be a number of things, but the evidence doesn't sit right. Given the value of the car 9+ years ago I would have expected the previous owner to have sorted it. Whether or not the seller's story is true, the fact that it's not been fixed by now indicates it's probably an expensive job, and one you probably don't want to get involved in.

IIRC that's about what I paid for my bonnet foam - it's a messy and time consuming job and a bit of a stretch but not too difficult to do.
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Thanks Doodle,

What about the shift from 1st to 2nd, is yours more noticeable than other shifts?

I also noticed that yours is a 95 model, does it have the digital odometer?

From what I have found the part orange indicators were unique to 95 model cars.

The seller is going to look into the airbag fault and let me know, not holding out too much hope to be honest.
Good point about it not adding up, but he did say he bought it from a private trader and that sounds like a private trader trick. Im sure it would fool most people. I was actively looking to see if all warning lights came on then went off, most people will only notice them if they stay on.

I assume that as per all other cars, the air bag light stays on for a little longer than all other light while it does all its checks.

Im guessing the market for these is quite stagnant at the mo as he said i was the only person in 3 weeks to come and view it.
No, but then my gearbox is on fresh fluid so perhaps to be expected.

Yes, I have the digital setup. I've seen part orange indicators as far back as 93 at least. I have white front/side currently but I'm almost tempted to go back to the white/orange setup.

It probably would back then, no doubt part of the reason for the MoT changes. To be honest I've never paid that much attention, but IIRC they go out together.
Also the foam from the bonnet has mostly peeled of, is this around £60 in materials?

A replacement one for my '97 car was about £100 plus VAT from M-B earlier this year.

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