weber carb and pertronix ignition upgrade

[johnr]

You could very well be right.  But the mech I take the car to and who rebuilt the engine warned me specifically about carb freezing and other cold weather problems.  I will have a look at the heat risers.
Thanks for the advice! 

[Bookwus]

Hiya John,

.......warned me specifically about carb freezing and other cold weather problems.......

Now that's really quite interesting.  I wonder why he/she would have done that.  I've lived in the Willamette Valley practically my entire life, and been into Volkswagens for 40 of those years, and this is the very first time I've ever heard of having to beware of carburetor icing in this area.  And your climate, being heavily moderated by the Pacific is even more moderate than mine.  Perhaps your mechanic is thinking about the relative humidity?

Even so, if the heater pipes are working correctly you should not be experiencing icing in any sort of conditions.  That's what's making me think that there might be something amiss with the heat riser tubes or, possibly, the choke.  The heat riser tubes, if blocked, are just a bear to clean out.  Much easier to leave just as is, or easier to replace than to clean out. 

[singlecab61]

I say check the choke. The choke is most likely closed too much. When it gets colder out, it will close more. A quick choke adjustment trick:

-Disconnect the choke power and tape it off so it won't short to something.
-Fully depress the accelerator once to set the fast idle and release the pedal.   
-Start the engine cold (i.e...Early in the morning.)
-Loosen the 3 small screws on the right side top of the carb enough to release the adjustment. (Where the choke power plugs into.)
-Rotate the choke clockwise until the engine starts to smooth out.
-Tighten the 3 choke screws.
-Shut off the engine.
-Reconnect the choke power wire.
-Restart the engine and test drive it.   

If you adjust your choke by the 3 little notches on the carb housing, there is a very good possibility the choke is not adjusted correctly. I have almost never had the choke correctly adjust and have it line up with one of the 3 notches. Even brand new chokes/carbs!

It is completely normal for the engine to fart and sputter when cold, the choke has not yet fully opened.

A good preset for the choke is:

-Again start out in the early morning.
-Remove the air cleaner
-Open and close the throttle arm.
-The choke should have rotated the ''stepper'' linkage clockwise.
-The throttle stopper screw should be resting on the second notch from the top of the ''stepper'' linkage.
-Adjust the choke until the throttle stop screw is set on this ''step''.
-Reinstall air cleaner.

This is all well and good if the rest of the carb is correctly adjusted to begin with.

The choke should be open roughly 1/4-1/3 of the way when cold. If it's closed too much, it will run like poo!

-Evan