Thanks Dee. The distributor was done by Jake Flemming and I haven't touched it. My thinking was that since the engine runs so well otherwise, that the bucking while coasting must be an adjustment issue of some kind. I'm no mechanic, but the only things I could think of that could be adjusted are the carb & the vacuum brake. The carb is the one I got from you, and works well - so could it be the idle speed? Also, I do have a spare distributor, also rebuild by Jake, that I could put on if you think that may be the problem. Thanks for the help. Iain