[Todd Gibbs]

Hi Guys,

Recently picked up a 1981 SL500 in beautiful Pastel Grey (81k miles). I have a few random things I need to solve and thought I would post them here in one lump. Here goes :-

1. The rpm needle rises when I start the engine and sits at 500. It never moves again until I turn the engine off (regardless of the engine rpm). Any ideas ?

2. The heater seems to be stuck on HOT. And after a while of driving the fan goes full-on for a while (making the car very very hot). I also noticed the dashboard is extremely hot. Is this a common issue and how do I go about tracking it down?

3. I noticed one of the catches had been removed on the soft top cover (that folders up/down to access/hide the soft top). I put it back on and closed it. Now it won't open when I pull the lever. (One side does, the driver-side doesn't). Is there a way to release it ?

4. The accelerator pedal has a lot of travel before it does anything. I read it is probably the linkage... is the right / a DIY thing to fix ?

Thanks so much for any help

Todd.

 

[jaymaynard]

Todd, welcome to the insanity!

I don't have wisdom to offer about three of your four questions. For #2, do you have automatic climate control, or manual? If it's automatic, which one is it: a row of vertical buttons, or a row of horizontal buttons? if it's a row of vertical buttons, that's the ACC system, used on 1978-1981 US-spec 107s. If it's a row of horizontal buttons, that's the ACC-II system, used on 1982-1985 US-spec 107s.

The bad news is that the ACC system is known to have problems, and in particular uses a servo made of unobtainium.

Also, it's properly referred to as a 500SL. The swap of the class letters to the front didn't happen till the 1994 model year, after the 107 ended production.

Finally, it's a good idea to fill in your profile and mention not only what car you have, but also where you are.

 

[rowdie]

You are a bit off Jay. The '78-'81 system is referred to as ACCII. (The bound to fail Chrysler design) The '82-'89 is ACCIII.
There is another variation on the European models. Not sure when it started. It has two dials at the bottom. There may be pictures of it in the EGv107 Sticky at the top of the page. European models may have the manual AC controls through out production.

 

[rowdie]

I checked. The EGv107 does not show the European controls with two dials at the bottom. It does show the others. http://www.benzworld.org/forums/r-c...manica-volume-107-aka-egv107.html#post4552418

 

[Todd Gibbs]

Thanks Jaymaynard,

Im not sure which climate control it is - it has the option code for air conditioning. In the vehicle it has 4 vertical sliders (two on the left and two on the right), and two dials (one for fan speed and the other for temperature).

I've updated my profile

Todd.

 

[jaymaynard]

Im not sure which climate control it is - it has the option code for air conditioning. In the vehicle it has 4 vertical sliders (two on the left and two on the right), and two dials (one for fan speed and the other for temperature).

Then you do not have the automatic climate control. That is a good thing on a 1981, since the ACC-II system (thanks Rowdie) is notoriously prone to breakage and essentially unfixable.

 

[rowdie]

Thanks Jaymaynard,

Im not sure which climate control it is - it has the option code for air conditioning. In the vehicle it has 4 vertical sliders (two on the left and two on the right), and two dials (one for fan speed and the other for temperature).

I've updated my profile

Todd.

You have the first AC controls. The European version is as you described. A North American version with cruise control and another dial is pictured in the Climate Control section of the Sticky at the top of the main forum page page, EGv107. http://www.benzworld.org/forums/r-c...manica-volume-107-aka-egv107.html#post4552418

 

[Todd Gibbs]

You have the first AC controls. The European version is as you described. A North American version with cruise control and another dial is pictured in the Climate Control section of the Sticky at the top of the main forum page page, EGv107. http://www.benzworld.org/forums/r-c...manica-volume-107-aka-egv107.html#post4552418

Mine looks exactly like this one :-

http://mercseller.com/lrg/481_16.jpg

Periodically it goes into over-drive and blows on full (with hot air). Then it calms down and returns to normal. I read somewhere that its to avoid (something) overheating ?

Todd.

 

[Aussiemerc]

Hot water valve

Exactly like mine (RHD). If it's always hot your water valve is probably not working. It is default "on". Could be vacuum related or the valve itself .

 

[Todd Gibbs]

Thanks AussieMerc, I'll take a look. Is it an Air-con system or not ?

Todd.

 

[Aussiemerc]

Hot water valve

Thanks AussieMerc, I'll take a look. Is it an Air-con system or not ?

Todd.

There is a hot water valve whether or not it has aircon. The valve simply shuts off hot water passing through the small radiator core inside the heater box. The fascia in your post has air (the switch with the blue swirl) . The water valve needs to close if you just want fresh air. Levers 1 and 4 need to be down so that the valve closes and the outside vents under the grilles also close when you use aircon. With no aircon the levers still determine airflow whether fresh or hot.If you look in the stcky section I did a post on the adjustment of levers in old style systems. There are vacuum lines controlling the functions activated by the levers and switches.
The fan speed switch (left in pic) is all electric whereas the aircon on/off is both electric and vacuum.