Lancia Beta Forum

Technical stuff => Fuel System Carb => Topic started by: wheelies on March 27, 2012, 09:19:36 PM



Title: carb set up
Post by: wheelies on March 27, 2012, 09:19:36 PM
Can Someone talk me through the process of setting up a Weber 34 DATA carb from a 2l FL spyder.
I have set up the tick over and the mixture, which seems to be running well when the engine is up to temp.
The choke setting is the one I'm not to sure of. I have tried to follow the Haynes settings but they don't appear to work?
Can someone give me in plain laymans terms how to set the secondary screw for the choke to operate in the 2 stepped stages of the automatic chokes. Surely there is a way to position the screw onto the steps when the engine is cold, assuming other parts of the carb. haven't been altered. 


Title: Re: carb set up
Post by: droptop on May 15, 2012, 09:08:26 AM
When the engine is cold, the choke cam should be fully rotated to the highest point of the lobe on which the fast idle screw rides so that's when I adjusted mine.
If the cam hasn't aligned with the screw, then the choke spring body needs to be rotated until it does.
At the start point, the buterfly should be almost fully closed across the throat of the carb to reduce the amount of air entering the combustion chamber and therefore enriching the mixture.
After a couple of minutes running, tap the accelerator and this should return the choke to the mid position with the butterfly partially open and the screw resting on the smaller lobe.
at this point, you need to back off the screw to the point where the engine is on a high idle. I set mine around 1000-1100 RPM to ensure a smooth idle, but not enough RPM's to cause the car to pull away too fast when you engage the clutch.
I'll take a look at mine tonight and see what direction you need to rotate the choke body in in order to engage the screw.


Title: Re: carb set up
Post by: wheelies on May 16, 2012, 06:32:47 PM
I think if the throttle screw is just clear of the main com section the engine revs. will increase when it lifts onto the second step then onto the third higher lift section. It is then you will have to adjust the revs back to an acceptable level.
This is assuming your butterfly valve is open a fraction, when you are on full choke.
Does this sound right?

Brian