For the last two years I have been battling a problem with my car that has
reduced the fun of owning it by at least 50 percent. I have asked for advice
on this problem before, but I hope that someone will have a new insight. My
problem in a nut shell is that my car runs very badly at idle and seems to
suffer from a vacuum leak that causes it to run very lean. Unless the needle
(B1DL) is set to full rich the car will barely idle at all. I have tried in
vain to find a vacuum leak using carb cleaner and the carb has been rebuilt by
both myself and Apple hyd. I believe that the carb is original to the car,
however the brass tag is missing so I cannot be certain. The rest of the car,
ignition, compression etc. is new or rebuilt and seems to function well as far
as I can tell. Using the colourtune plug the color is orange, but if I adjust
it until it starts to turn blue the car will start to miss and stop running.
If I hold my hand over the mouth of the carb to choke off the!
airflow the idle jumps up, indicating to me at least that there is a vacuum
leak or the carb is just too lean. On the vacuum gauge the manifold vacuum is
about 18" at idle jumping to 21" when I manually block the carb off. I have a
spare intake manifold that I am going to install this weekend to see if that
makes a difference. Has anyone had trouble with the intake cracking or
becoming so porous that it causes this kind of problem? I also plan to block
off every vacuum outlet coming from the carb to eliminate every possibility of
a leak. I hate to let this thing beat me, but a weber is becoming more and
Thanks for letting me rant, any advice is gratefully appreciated.