weber carburetor troubleshooting
Posted 11 November 2012 - 12:28 PM
Posted 11 November 2012 - 03:23 PM
How did you determine that you have no vacuum advance??? No carb made after the late '60s has vacuum advance at idle. It's only when the throttle is opened that vacuum is applied to the vacuum advance on the distributor.
Posted 11 November 2012 - 11:48 PM
So your problem is something else. Have you asked in a Honda forum?
Posted 12 November 2012 - 05:46 AM
The vac advance signal from the carb is to create an advance in timing as the throttle is opened. On a weber, if you hit the pedal too fast, the vac signal is too quick or non-existent and the dizzy doesn't have time to react. The webers are a bit tricky to adjust. You want the butterfly closed as much as possible when you do the tuning. There should be no vac signal at idle, but as you crack the throttle, you will see it jump up close to manifold vac. When you tune the weber, just keep in mind that having the butterflies closed as much as possible is your primary goal and tune around that.
Sadly, I prove this nearly everyday!!!
Posted 12 November 2012 - 12:28 PM
yes, adjusting idle-mixture must be done with throttle butterflies 100% closed. And choke butterfly 100% open. Just like any carburetor.