17-11-2017, 09:09 PM
(This post was last modified: 17-11-2017, 09:11 PM by Reckless Rat.)
Nick,
Have you checked that there isn't an air leak at the carb/manifold flange interface. The Zenith 26VA is made from very soft alloy and the flange face can often be distorted, causing air to be drawn in raising the tick-over speed. It's easily remedied by taking the carb off the car and rubbing the flange face on some emery paper on a firm flat surface.
Failing that a slightly stronger spring on the linkage might help. I backed mine up with a coil spring between the linkage arm and the fuel pipe to the pump (the same spring as used on the brake light actuator).
Have you checked that there isn't an air leak at the carb/manifold flange interface. The Zenith 26VA is made from very soft alloy and the flange face can often be distorted, causing air to be drawn in raising the tick-over speed. It's easily remedied by taking the carb off the car and rubbing the flange face on some emery paper on a firm flat surface.
Failing that a slightly stronger spring on the linkage might help. I backed mine up with a coil spring between the linkage arm and the fuel pipe to the pump (the same spring as used on the brake light actuator).