Hi guys!
Yestererday i failed exhaust emission MOT test, the result of CO level was 5.43%. I was told that this could be cased by wrong adjustement of carburettor. Could anyone step-by step explain to me what the shown screws are for and haw can I properly adjust it?
It's very urgent case becouse tomorrow I'll have to retest my Volvo.
Here is arrowed idle adjustment, mixture adjustment is at carb base, right side when looking this image, there is just hole and screw is at bottom of hole.
Here is the hole with mixture adjustment screw at bottom left, facing almost to camera.
Oh yes, this is 34-34 Z11, but I guess it should be similar?
my dad 340 failed it MOT for the same reason. Ive heard these solox units for the 1.7 can be hard to adjust - in that you cant get the CO low enough. There is a post here somewhere that comments that float can sometimes need changing - they are plastic and absorb petrol and loose their buyancy. Wouter ( from holland ) posted it. He suggests getting a new one from renault.
The mixture adjustment screw is in the place that is pointed in the last picture
The idle screw is in the top of the carb. In the first picture there are 2 jets and one screw. Is that one.
To adjust it, first adjust the idle to 900rpm.
Then you kick the acelerator and adjust the misture screw until when you kick the acelerator (to arround 3000 rpm), when the revs come down it stops in the 900rpm. The better way is to adjust it until it goes little below 900 rpm and then come to 900.
My english is not vey good but I thinck that you understand what I'm trying to explain
| 92' 965 Turbo 16v | B204FT - 190hp |
Had: 90' 340 GL + Turbo | B18 FT | Koni's | Alpina White |
I'm afraid in Z10 there's no mixture screw in that place. I was looking carefully for that little bastard but i couldn't find it. Indeed the idle jet seems to be the lower one showed on my first picture (is it the same?). What jtbo's showed on his first picture is idle speed adjustment screw and it's responsible only for dosing fuel not for mixing it with the air. So that's why I'm a bit confused and still looking for solution
the idle speed is adjusted on the top of the air cleaner through the hole, you'll need a long screwdriver.
The mixture screw is as in that picture, in the baseplate of the carb, pointing towards the front of the car.
TBH its in the Haynes or any carb book, can you not bung your MOT tester a few notes and just get him to twiddle it down a touch, once the equipment's attached it only takes 2 minutes.
Is that definately a solex guys? Looks much like my Weber, I know the weber was there to replace the solex, so it will look similar... but that looks identical top down. I'd be tempted to ask the guy as Andy said, at least it'll be on a gas machine, even if you twidle the screw.
If it is a Solex Z10 it's not like any I've seen before - the top of the venturis are all wrong and the single acc.pump jet nozzle enters the primary throat above the atomiser bar, etc., etc.
It looks awfully like a Weber 32DRT or similar (the aftermarket replacement for the Solex 28-34 Z10 CISAC). (saw a few over the years when pelicans tried to claim parts warranty on them).
don't know much about them except the baseplates seem just as prone to warping as the Solex.
mac wrote:It looks awfully like a Weber 32DRT or similar (the aftermarket replacement for the Solex 28-34 Z10 CISAC).
As it turned out it's some kind of Weber carburettor, Solex had to be replaced by that one long time ago.
I've taken the carburettor symbol from owner's manual so ... sorry my fault
Yup I've found the mixture screw (hidden into that elbow case).
We've only seen the top of his carb. 
