Engine races when cold.

[bete frlo]

Hello and happy new year.

Does anybody know how to adjust the engine idle speed when things are cold and its running on choke. (2.0l Aircooled twin Solex).

After a few miles the idle speed is spot on, but when cold it races at a scary pace, I can almost drive to work without touching the throttle pedal.

I have given the carbs a clean up, and wonder if its simply an adjustment to be made, especially as it runs great once warmed up (off choke).

I have checked the Haynes manual but its all a bit vauge and confussing.

[VWCamperfan]

I may be wrong here but if I remember correctly there should be a stepped metal plate on the outside of the carb attatched to the choke valve which turns with the choke. This will open the accellerator slightly when the choke is closed by pushing an adjuster screw outwards which is part of the accellerator mechanism. This adjuster screw needs to be turned anticlockwise to allow the accellerator to close slightly. Do this when its cold to reach the desired rpm.
My apologies again if I am thinking of a different carb setup but hopefully this is correct!

[bete frlo]

Many thanks, I will investigate further............

[Laurie]

It is meant to rev high when cold. VW set them at over 2000RPM. Adjustment is a 7mm nut on a threaded bar that comes from the throttle are to near the choke. If you loosen the top nut, you can then wind the bottom nut down to reduce the amount of throttle opening. Go too far and you'll flood everytime it's on choke. Do the adjust with engine cold.