SL-Class (R129) 1990-2002: SL 280, SL 300, SL 320, SL 500, SL 600, SL 60 AMG

SL/R129: Fixing an SL320, worth it?

Old Jun 24, 2015 | 02:56 PM
  #1  
Mijaeus's Avatar
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Subaru Impreza WRX 2011
Fixing an SL320, worth it?

Hello,

Here is my current situation: my parents are life long Mercedes users, to a point that all their cars have been Mercedes for the past 15-20 years. One of the cars that has never left the family is a 94 (or 96, I have to check) SL320 that has aprox. 140k miles (more then half are highway). This car doesnt see much use lately, its kept parked at my parents house. I currently drive a 2011 Subaru Wrx. When I was growing up, I always liked the 320 but it was "promised" to my little brother once he turned 18. Well, now that he did turn 18 he got himself a truck and doesnt really care about the merc and my parents dont really care anymore either :P So, I was told that I could have it if I promised to take care of it.

So, this brings us to my question: would it be worth it to fix? I'd likely sell my car and I guess I could use somewhere between 10-15k to fix the 320.

The cars work fine but it does have some problems:
- engine starts to overheat if the car is left running and not moving. It has actually never left me stranded, but once I was in a traffic jam and the temp. needle got very very close to the max, and I could see a little white smoke coming out from the engine comparment. Temperature went down once I managed to get on the highway. I guess the fans might be on their way out?
- according to my mom, the 1-2 gear sometimes gets stuck. I havent experienced this but I will take the car out this weekend and drive around checking what else I notice.
- the wiring is probably on its way out. This car spent around 8-10 years in the country under heavy rain and mice. The dashboard used to light up (like 8 icons lighted up on the right side of the dashboard). According to my parents it was taken care of.

Other than that, the cars works fine. Interior is in excellent shape, and the paint needs a good detailing and it'll look good.

Now, my plans for this car would include a new wiring harness, rebuild the engine, change all seals, etc. My main concern is with the gearbox as it would probably be hard to fix, maybe I'll have to replace it.

So, would this be a bad idea? Money pit?

Fixing an SL320, worth it?-9b0zbav.jpg
Fixing an SL320, worth it?-qaugzn4.jpg
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Fixing an SL320, worth it?-kzlvolk.jpg

Edit: the 10-15k estimate is because I live in south america The cheapest sl320 where I live is going to 20k, and there arent many listed.

Last edited by Mijaeus; Jun 24, 2015 at 03:01 PM.
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Old Jun 25, 2015 | 01:54 AM
  #2  
MB-Dude's Avatar
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From: Covington, WA
'96 SL600, '05 S55 AMG, '06 C230
Frankly, I don't think the repairs needed will be as expensive as you think. The wiring harness is probably in bad shape not because of the country and mice, but because of a choice of material when Mercedes built the car. The bumpers do not suggest a 1994 but it could be a '95. The overheating may be nothing more than a very thorough flush of the cooling system. Same for the occasional 1-2 gear issue - flush the transmission fluid and change the filter. And the dashboard lights might be as simple as a bulb or two built-out. If the car is in reasonable shape AND you like the car, then why not put a little money into it? Body is reasonably clean and you say the interior is also in good shape. Bottom line, if you like the car, then don't be afraid to invest a little money into it to solve what may be simple issues.
Cheers,
Jeff
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Old Jun 25, 2015 | 03:20 PM
  #3  
sapphirexae's Avatar
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2002 Silver Arrow, Pano
Originally Posted by MB-Dude
The bumpers do not suggest a 1994 but it could be a '95.
You are correct that it is not a 1994, but incorrect that it could be a 1995. Only 1996+ cars have those bumpers and the two opening fender vents. This car could only be a 1996 or a 1997 (the climate control style would prove which one as they changed in 1997). This all being said, someone put 1990-1995 wheels on this car.
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Old Jun 27, 2015 | 10:17 PM
  #4  
FATHERTIME's Avatar
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From: Yorba Linda CA
94 SL320 98 SL500 99 SL600 07 SL55
I just finished restoring a 94 SL320 to new condition, it's a great car, well worth the effort.
I'm sure I put more in mine than you'll need. From your post I think you can do it for not a lot of money.
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Old Jun 29, 2015 | 10:43 PM
  #5  
Pete S's Avatar
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From: Philadelphia
1996 SL500, 2008 R350 4Matic
Thats definitely a 96, the two openings on the fender, the 6 slat grille (went from 7 to 6 in 1996) and you have the oddball IR sensor underneath the rear view mirror which is a 96 model year only thing. That being said if the cost to get the car in very good condition is more than say 5-6k than absolutely not. I see people buying 500s in decent condition for just a little bit more. throwing 10-15k on any R129 barring a 600 or a special edition AMG (very rare) is a terrible idea.
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Old Jun 30, 2015 | 09:28 AM
  #6  
FATHERTIME's Avatar
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Joined: Dec 2014
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From: Yorba Linda CA
94 SL320 98 SL500 99 SL600 07 SL55
All you need engine wise is to replace the head gasket and while the head is off resurface it and do a valve job including replace valve seals. The wire harness is a must. Trans should be ok just service it and see.
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Old Jun 30, 2015 | 11:20 AM
  #7  
sapphirexae's Avatar
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2002 Silver Arrow, Pano
Originally Posted by FATHERTIME
The wire harness is a must.
Incorrect as this is a 1996. The corroding wire harness issues did not affect 1996-2002 models.
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Old Jul 12, 2015 | 10:42 AM
  #8  
FATHERTIME's Avatar
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From: Yorba Linda CA
94 SL320 98 SL500 99 SL600 07 SL55
Good to know as I just added a 98 SL500 to the garage and beginning to bring it to new condition. Those wire harnesses are kinda pricey>
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