[W126 Coupe] Getting my 560SC to shift gears earlier?

[Dawid Loubser]

Hi Dick,

Thank you for the advice. I had my suspicions this was the adjustment,  
I just needed confirmation.
On my car, it's a horisontal sliding adjustment, which connects to a  
cable running to the
transmission.

I adjusted it, and after two iterations, got it just the way I like it.

thanks again, and all the best
Dawid


On 08 Jan 2011, at 6:45 PM, Dick Spellman wrote:


> Hi David,

>

> You need to adjust the control linkage between the throttle cable  

> and the transmission.  The control linkage for the transmission  

> shift point is a steel rod running vertically down your firewall.   

> It connects on one end to the throttle linkage on the intake  

> manifold and on the other end to the transmission.  When you depress  

> the gas pedal this linkage moves the throttle and this rod to  

> precisely control your rpms while holding the shift points on the  

> transmission.

>

> Based on your description, there is too much slack in the rod.  If  

> you locate the rod, you will note a nut of either 10 or 13mm that  

> permits the rod to be lengthened or shortened.  In your case, you  

> want to shorten the rod.  The correct adjustment is outlined in the  

> service manual.  There is no harm in your loosening the nut and  

> making an incremental adjustment where you make it shorter.  This  

> will get you to the correct shift point with one or two tweaks.

>

> Regards,

> Dick

>

> On 1/8/2011 9:16 AM, Dawid Loubser wrote:

>> Hi All,

>>

>> After some pretty major work done to my 1990 560SEC (Euro,ASR)  

>> including an engine replacement

>> (which I am very happy with, as per an earlier message to this  

>> list) my only remaining complaint

>> is that my car shifts gears too late, making gentle driving  

>> uncomfortable.

>>

>> In "E" mode, under gentle (fuel-efficient!) acceleration, my car  

>> used to change gears

>> around 2,500RPM or even less, depending on throttle pressure. Of  

>> course, in "S" mode,

>> it held on for longer, like it's supposed to.

>>

>> Now, in "E" mode, it changes at 3,000, even 3,500 RPM during gentle  

>> driving, which I

>> find unfavourable for my daily driving.

>>

>> Surely there is a reasonably simple adjustment I can make myself to  

>> rectify this?

>> This behaviour is consistent across all gears, so basically I would  

>> like to drop the

>> RPM of gear changes by about 1000. Could this be related to the  

>> throttle position

>> sensor? I say this, because, at about 2,500RPM, if I almost  

>> completely release the

>> throttle, it does change. I would like this behaviour with moderate  

>> throttle applied in

>> "E" mode, like it was.

>>

>> For performance driving, the car is a beast (great). In "S" mode -  

>> and flooring it -

>> changes are very positive and close to the RPM limit.

>>

>> Any help appreciated to restore what used to be a wonderfully  

>> balanced character to

>> my gear changes! I don't feel like taking it back to the shop  

>> unless I can help it,

>> I'd rather understand the mechanism myself.

>>

>> I adjusted my throttle linkage to remove quite a bit of play (in an  

>> attempt to cure

>> this problem) but, despite being *much* happier with the lack of  

>> play now, shifting

>> characteristics have not changed at all.

>>

>> kind regards,

>> Dawid

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>

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> Postings remain property of MB Coupes, L.L.C.