3 replies to this topic

[mars red mike]

I had my carb in bits yesterday and noticed that the throttle disc had something fitted to it, like a small spring-type thing. Its the same as this one
http://www.minispare...ty=pb&pid=42387

My question is a) what is it? and b) is it worth removing it as I would have thought that it would affect flow and I have got another throttle disc without one on.

ta

mike

[Dan]

It's an over-run valve. It is supposed to open when the manifold depression is particularly savage to allow some flow through the carb when you suddenly snap the throttle shut on a fast running engine. To stop the traditional stalling at a motorway junction. They work brilliantly when they are new but very rapidly wear out. They do provide some obstruction as you would expect. Get rid of it.

[mars red mike]

Cheers Dan.

[1.3Cooper]

not had the mini long so no experience yet! but on Range Rovers they caused various problems when the springs get weak - we used to replace the disc to get rid of them or failing that solder them up - sorts out the high idle speed and running issues but still forms an obstruction.