Sorry - another of my hassles. Many thanks to those who responded to my thermostat problem.
About a month ago I stupidly put some diesel fuel in my petrol spacecruiser - don't laugh I feel a complete prat about this. My local garage cleaned the thing out for an exhorbitant price and it ran again, albeit roughly at first. However, ever since this incident the idle speed has been really excessive - 1500 - 2000 rpm. I've been through the autochoke mechanism and obviously the throttle stop screw but nothing brings the revs down - any ideas?? - (#1321) David Woollard-Kingston, 30 Oct 01

Check that the the throttle valve is not sticking. With the engine hot, if you adjust the idle speed screw does it have an effect on tickover? - (#1326) Ian Dunse, 31 Oct 01

It might be worth checking any vacuum advance pipes that may have been disconnected whilst the work was being carried out. These will be below the throttle valve. If air is being sucked in it will increase the idle speed
Hope this helps Barry - (#1359) Barry Powell, 4 Nov 01

if when u adjust the idle speed screw and the revs dont drop,check the idle mixture if its too rich it will tickover a lot faster - (#1372) steve, 6 Nov 01