weber 32/34 carb probs

[dan-hipgrave]

I have just fitted a weber 32/34 dtml and K&N filter onto my mk1 1.2 and the car is now undriveable - when i start the car without pressing the accelerator the revs will rise right up to around 5000rpm and then drop off until the car stalls at about 1000rpm - i know that the carb will need setting up for the engine but i didnt know that it would be this bad - i cant even get it to a garage for them to set it up..is there any way that i can sort it myself so that it is at least not revving itself to death and then stalling?

[Adam]

Firstly was the carb in good condition when you put it on, all freely moving etc. What engine was it jetted for when you had it.
Are all linkages and pipes securely on, is the throttle linkage etc moving and returning back to idle.
Is the idle and mixture correct.
And did you use a t-piece or did you use a vacuum seprator.
Did you remember to put the cork gasket on top of the carb when you fitted the K&N. Could have an air leak from inlet manifold or carb somewhere.

[dan-hipgrave]

woah questions, questions...ok - the carb was in good condition when i got it, all pipes are securely on, throttle moves back to idle, not sure about the idle and mixture settings (how do i adjust these?), i used the vapour seperator, no the K&N doesnt have a gasket fitted - would an air leak cause it to rev really high without any gas and then drop off and stall? I wouldnt have though so...but then i dont know much about this sort of thing as you probably can tell :oops:
Cheers for your help mate :D the car is currently stuck in my works carpark about 8 miles away so i think ill be calling out a mobile tuner or summat unless someone can give me advice on where on the carb i can adjust it and how to do it.

[Adam]

I think, well you do on the Pierburg carbs that under the K&N filter there should be a cork gasket. If this wasn't fitted then this may cause the mixture to be very lean. If the mixture is lean then the idle will be quicker, higher rpms.Sounds like your symptoms doesn't it, try that.
Then the mixture is becoming so lean that the idle falls down and stalls.
Try the gasket off a mates car of something see if it helps.

[dan-hipgrave]

cheers for your help mate i'll see if i can find a gasket for it..

[Snowface]

don't worry about the cork gasket.

it only stops dirty air going through the gap rather than through the K&N. That is its sole purpose.

The mixture screw is at the back right of the carb down the bottom insude a tiny hole.

Idle screw is nect to throttle linkage.

[dan-hipgrave]

cheers for that mate, i'll have a look this weekend, ive had to put the car back to standard just so it could be driven home :( so ill bolt the weber back on and see if i can adjust it meself to get it running properly

[Adam]

You could drive to your local garage, standard carb etc, take the weber with you and then ask them to fit and set it up.

[Dave448]

its an air leak ... get a bit of tube ... poke one end around the base of the carb and the other in you ear .... you will hear a sucking noise ...thats where the air leak is ... we had loads of bother around the adapter area .. we used loads of Hylomar gasket stuff .. oh ..and try not to over tighten the nuts on the studs .. you can strip the thread ................(bin there dun that..Doh!)

:roll:

[MechaT]

You may well have a leak but you can't just stick the carb on and expect it to work.

Assuming the ignition timing is correct, screw the mixture adjustment screw all the way in, then screw it out by two turns.
Start the car and try to get it running.
Keep unscrewing the mixture screw half a turn each time and starting the engine when it stalls until you can manage to keep it running.
Then chug (and you will chug) down to the garage.

That's what worked for me.

[rikih]

i had a few problems with mine too, still dont know what it was but taking off the fuel return stopped it stalling and now runs fine?! quite weird really

[Dave448]

you want to keep the return as it limits the pressure acting on the needle valve... the mechanical pump 'pulses' the fuel and your just wating gas otherwise
HTH
:)