Jaguar Repair: Adjusting Choke on 4.2 XK engine, linkage problem, throttle shaft

Question
My'67 E-type coupe had a recent engine rebuild. Runs terrifically. Over the past couple of months however the choke seems less and less effective. It still functions but not nearly as well as it once did. Almost as if the cable stretched so it what "throttle" up as high. Is there an easy fix for this?

Answer
Hi Keefer,
The three "HD" type SU carburetors on the 67 "E type" have the jet adjusting screw mounted down low on the side of the carburetors and if you have someone open the choke, you will see the lever lift the adjusting screw upward. This makes that carburetor richer in mixture. At the same time you will see a rod with a short plate and an adjusting screw on it go down close to the throttle shaft which opens the throttle. (that adjusting screw is the "fast idle screw".)
If you have a cable problem or lower linkage problem it will not lift the jet adjustment nor lower the fast idle screw. Look at all three carburetors.
To get the adjustments correct you will need a service manual as it is far too much to cover in E-mail.
Howard