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  #1  
Old 05-03-2006, 11:49 AM
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Join Date: Jan 2002
Location: England
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Transmission adjustment. + does it differ for petrol/diesel?

I want to adjust the shift firmness (and have a play with the shift points while I'm there, for a laugh) of my 190E petrol (2.0 euro - but same as the 2.3 8v really).

Doing a bit of a search is interesting - every thread talking about adjusting the bowden cable and modulator involves only people with diesel cars! Really! Why is that? Is it only the diesels that have the adjustment? Or is it only the diesel owners that are keen enough to get adjusting them?

They spoke of a bowden cable that comes from the firewall to the valve cover. I can't see anything of the sort on my M102 engine! Is it different? Where should I be looking? Is it a dedicated cable that goes between the throttle linkage and transmission?


Presumably the modulator is the same on all models. Can I adjust it in my driveway with no tools (pull rubber cap out, pull metal bit out and turn?). I have access to vehicle lifts, but they're 1/2 hour away and I would have to find the time. Plus I feel like playing NOW!

cheers,

Russell

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190E's:
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black 2nd owner
http://www.maylane.demon.co.uk/190esmall.jpghttp://www.maylane.demon.co.uk/190esmall2.jpg
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  #2  
Old 05-16-2006, 07:09 AM
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Well.. no replies so I guess I'm replying to my own thread.

I adjusted my transmission with the car up in the air. It's a bit of a squeeze to get to the adjuster but not too bad, a long pair of pliers helps. Make sure the adjuster 'key' doesn't fall out or you could lose it. I turned it 1 turn anti-clockwise, and it smoothed out about 15% - not a huge amount so I might go back and do it some more. It's on the passenger side (Right Hand Drive car!!).

Russell
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190E's:
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black 2nd owner
http://www.maylane.demon.co.uk/190esmall.jpghttp://www.maylane.demon.co.uk/190esmall2.jpg
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  #3  
Old 05-16-2006, 11:59 AM
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Join Date: Aug 2005
Location: Palmdale/Ventura, CA
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I am curious, you turned it 1 whole turn anti-clockwise ?
The book seemed to suggest smaller amounts like 1 or two notches, maybe 1/4 turn.

That you can go whole turns is good to know.

As a diesel owner I can only point out that a diesel engine has no natural vacuum from the manifold to help sense load on the engine.

A gasoline/petrol engine produces intake manifold vacuum which is used by the automatic transmission to sense load and adjust shift points.

We diesel drivers have to have a vacuum pump and then interpret throttle position to regulate vacuum. A messy business.

As for the bowden cable, I cannot say for sure if it is a diesel only thing.
I do know that my non-turbo diesel does not have one, the turbo diesel does.
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  #4  
Old 05-16-2006, 12:12 PM
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Quote:
Originally Posted by rhodes2010
I am curious, you turned it 1 whole turn anti-clockwise ?
The book seemed to suggest smaller amounts like 1 or two notches, maybe 1/4 turn.

That you can go whole turns is good to know.

As a diesel owner I can only point out that a diesel engine has no natural vacuum from the manifold to help sense load on the engine.

A gasoline/petrol engine produces intake manifold vacuum which is used by the automatic transmission to sense load and adjust shift points.

We diesel drivers have to have a vacuum pump and then interpret throttle position to regulate vacuum. A messy business.

As for the bowden cable, I cannot say for sure if it is a diesel only thing.
I do know that my non-turbo diesel does not have one, the turbo diesel does.
Thanks - that makes a lot more sense now, the diesel vacuum issue!

Yes I turned it a whole turn. And will go further. I had the box rebuilt 4-5 years ago and the builder said he set it up with a firmer shift to give it more sportiness. Was very very effective too. But now I have a 16v to drive like that, the 2.0 can do the super-smooth auto shifts thing instead.


Rsussell
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190E's:
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black 2nd owner
http://www.maylane.demon.co.uk/190esmall.jpghttp://www.maylane.demon.co.uk/190esmall2.jpg
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  #5  
Old 06-14-2006, 04:20 AM
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Join Date: Jan 2002
Location: England
Posts: 1,841
I turned it another turn or more, and it had a very slight flair between 2nd and 3rd gears, so I tweaked it back a bit.

Nice smooth shift now although there's it can still drop into the next gear a tiny bit harshly (compared to autos in newer prestige cars) if off the throttle..
__________________
190E's:
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black 2nd owner
http://www.maylane.demon.co.uk/190esmall.jpghttp://www.maylane.demon.co.uk/190esmall2.jpg
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  #6  
Old 06-14-2006, 10:54 AM
GVB GVB is offline
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Join Date: May 2006
Posts: 178
I would really reccomend if you are going to mess witht he modulator pressure to use a bar gauge and do per spec of color and type, 722.3, 722.4..etc. You could be limiting the life of the transmission. The reason for the diesel owners messing with the pressures are they really do not know what they are doing and should be going after the vacuum switches on the top of the valve cover or side of injection pump that are broken.

Just a thought from someone who has seen this a million times over.
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  #7  
Old 06-14-2006, 12:15 PM
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Join Date: Jan 2002
Location: England
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Quote:
Originally Posted by GVB
I would really reccomend if you are going to mess witht he modulator pressure to use a bar gauge and do per spec of color and type, 722.3, 722.4..etc. You could be limiting the life of the transmission. The reason for the diesel owners messing with the pressures are they really do not know what they are doing and should be going after the vacuum switches on the top of the valve cover or side of injection pump that are broken.

Just a thought from someone who has seen this a million times over.
Do you mean that even if you are adjusting by the 'seat of the pants' you should use a bar guage as well? Or that I should ignore the seat of the pants feel and only set it to factory spec by using a bar guage?

When I had it reconditioned they set it up all hard(ish)-shifting like this (intentionally) which was presumably different to the factory spec.

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190E's:
2.5-16v 1990 90,000m Astral Silver
2.0E 8v 1986 107,000m Black 2nd owner
http://www.maylane.demon.co.uk/190esmall.jpghttp://www.maylane.demon.co.uk/190esmall2.jpg
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