[R129 SL] R129LIST Digest, Vol 30, Issue 24

[Peter Shelton]

Hi Matthias,

I appreciate your comments in that Mercedes are fine cars - that is why many 
of us own them.  You are correct in saying that cars that are older than say 
5 years are prone to problems, and in many cases they are specific to the 
temperature, humidity and general conditions the cars are subjected to.



If the car is little used, or left outside with minimal protection, the car 
will be prone to more issues than other similar cars.  Mercedes Benz (like 
many manufacturers) can not be expected to test and subject a vehicle (for 
the prices they are currently being sold at) to all weather conditions. Time 
is also a good indicator of how problems progress, but items will fail.



For instance, vehicles in Singapore are subjected to very hot conditions. 
When Mercedes Benz manufactured the vehicles from about 1996 to early 
2000's, the wiring loom came below the engine (presumably to save money on 
cable).   The system was 'tested' and no problems were experienced during 
the tests. In New Zealand, there are a lot of imported cars here, and so 
imported MB's are relatively 'cheap' compared with the US or European 
prices.  The cable used apparently had 'captan' or a 'captan' (plasticiser) 
similarity, and this degrades with heat.  When imported to NZ after a few 
years use in Singapore, we have had a number of failures with wiring looms, 
and the loom is replaced.   Cost is about 2,500 euros to repair. 
Incidentally, this problem is not dissimilar to the 'green slime' seepage 
that is emitted from electrical, fire alarm, etc cables manufactured from 
about 1968 to 1980, where the plasticiser begins breaking down and is 
changed to a green goo, commonly referred to as green slime.



In vehicles, there are failures especially with electronics, some is from 
corrosion from environmental factors, while others are just plain component 
failures.  Now the 129 series like some other models of the time, are very 
advanced electronically, even when compared with today's vehicles.  However, 
capacitors (voltage storage/ suppressive devices) 'lose' electrolyte, or 
just dry up and fail to operate correctly, and sensors stick or have 
corrosion on electrical contacts.  Hence the problems with dash lights etc. 
Given that the 'circuit boards' are not heavy weather sealed (IP65 rated) 
then weather and storage conditions (especially salt air - if you live 
within about 40 miles of the coast), if the coating on the circuit boards 
decays (assuming that there is a coating!). If you pull apart an old 
'computer', wiper controller or door lock etc, you will find some corrosion 
on the boards.  They have aged (just like we do).  CRC Zone 240 sprayed on 
the boards will give added protection from moisture and salt conditions 
(used also on washing machine circuit boards to help repel moisture).  [ 
Note: In my opinion, a glass of good red wine inside us frequently (as we 
age) can also help to boost our antioxidants and help our 'human circuit 
boards' to function a little better!!]



There are a number of 'tinkerers' that own Mercedes and yes, I agree that 
some of the problems will be caused by such human factors. We all want to 
save a few Euros, dollars, deutschmarks, pesos, etc and it is a hobby for 
many of us, so some problems will be brought on.  One thing generally about 
Mercedes, if you are having problems trying to remove or access something 
(apart from the heater!), have a cup of tea/ coffee, and rte-thing and 
re-try the approach, as access to nearly all Mercedes parts is very easy!. 
The CD manual certainly takes guesswork out of the equation.



I am and Electrical and Services Engineer (designer and trouble-shooter) and 
deal with issues on a day to day basis. Our 'family' has some 11 vehicles 
and I carry out most of the maintenance requirements.  There are some thinks 
just not worth the time and friends with businesses, can fix them much 
quicker.  In my opinion, unless you are experienced (and have the correct 
tools), forget self fixing the air-conditioning system (you need a set 
gauges, nitrogen, be able to weld, etc), tyres and balancing, mufflers, and 
electronic circuit boards.  I fix my own circuit boards [like Jan (the 
flying Dutchman and the Radar tracking inventor - also another Electrical 
Engineer)], and we have all the tools and many dollars of test equipment. 
It is great to try to repair issues as life is a learning experience.



Well Matthias, after all this, I am really reinforcing that any vehicles 
older than 5 years, and when subjected to varying environmental conditions, 
will develop maintenance issues that are inherent within the framework of 
original design and manufacture.  R129 Rag Top controls and mechanism, the 
roll bar and dash etc are all real examples of what happens with no 
tinkering, just aging and lack of use.  If rams are not used in the roof, 
corrosion does occur and the rams fail!  Fact of life!.  This forum is great 
for asking questions, offering answers, and brings us together 
internationally to confirm that we all have the same interest and enthusiasm 
for our 129 vehicles, many of us have experienced similar problems, and we 
are here to help.



Have a great day in the Universe, wherever you are, Lovely here in New 
Zealand, but a bit chilly - need a good Dutch or Brazilian coffee to warm me 
up!



Cheers, Peter S.



----- Original Message ----- 
From: "Matthias Fouquet-Lapar" <fouquetlapar at free.fr>
To: <r129list at mbcoupes.com>
Sent: Thursday, June 28, 2007 6:11 PM
Subject: Re: [R129 SL] R129LIST Digest, Vol 30, Issue 24



> There has been a problem within a certain time frame with evaparotors, 

> both on W140 and R129. Alhough it's a well know problem, I would be 

> interested to hear what other car manufacturer would pay to fix a problem 

> on > 10 years old car.

> Some of the comments on this list regarding A/C are just frightning, like 

> the one who was thinking about charging more gas because the cooling ws 

> intermittent. The R129 (in particular later models) have a _lot_ of 

> on-board diagnostics which let's you diagnose the problem.

> Otherwise, a pair of standard gauges will do it. It also assumes that you 

> know what you are doing of course. I do all my maintenance, including A/C 

> work, on my 500SL and 500SE (W126). I converted my 500SE to R134a 3 years 

> ago without a problem (replaced only the dryer) and it has been cooling 

> fine since then.

> I'm German, living here in France, and have access to all Mercedes 

> documentation which really helps. There are also exceptional good (German) 

> mailing aliases which even include specialists from the factory who build 

> the cars.

> Frankly, some of these discussions on this mailing list are frightning to 

> me (when it for example gets to the roof) and my impression that 90% of te 

> problems are home-made or an original minor fault is turned into a big 

> project because of ignorance.

>

> These are extremely fine cars and will last forever if you take correct 

> care, have access to the right documentation and some limited amount of 

> tools

>

> My 0.02 Eur

>

> - Matthias

>

>

> The MB Coupes Website!

> R129 SL Mailing List