[TR] Slow idle drop

[Dave1massey at cs.com]

It is more likely to be the vacuum operated over-run valves.  They are 
mounted on the side of the carb next to the throttle shaft.  Their job is to 
open up with vacuum gets high enough to cause excessive emissions.  There is a 
diaghram inside and reacts to the vacuum and opens a valve against an 
opposing spring.  If the spring tension is set too low it will open prematurely 
and close slowly.

You can identify them by the small tower that extends straight out with an 
adjust screw in the middle.  The proper way to adjust these is with a vacuum 
gauge on the car so your rebuilder may not have been able to adjust them 
properly.  Try loosening up the lock nut and turning the screw in a half turn 
or so and see if that changes anything.

Good luck.

Dave

In a message dated 5/7/2012 2:39:53 PM Central Daylight Time, 
eoot at citlink.net writes: 
> I recently installed professionally rebuilt ZS carbs on late TR6 engine. 
> I'm
> having an issue I hope to get some advice on.  After running at speed, say
> 2500 to 3000 rpm, and then coming to stop, the rpm is very slow to drop to
> normal idle.  I would say it takes about 10 seconds to settle down. The
> problem is also evident when up shifiting, as the rpm stays high between
> gears.  I have inspected the linkage and don't find that it is hanging up
> anywhere. Is it possible though that it could be something with the way I
> reinstalled the linkage?  Or could it be that the vacumn advance is not
> functioning properly, or????