Solex Cisac Idle Air Compensation

The B230K engine well fitted with Solex Cisac carburetor. This 'modern' caburetor is well equipped more with pneumatics equipment. One of them is the idle air compensator unit mounted, which work based on pneumatic air/vacuum. The working principle is very simple, at the same time air-cond compressors engaged, a pneumatic valve mounted on firewall will be activated. It simply sucks air in, connected to the idle air compensator on the carburetor. The unit then through its' 'handle' throttles up the car. This balances idling speed both with and without air-cond.

labelled #94

And for me, the unit had broken. The car idle speed drops once air-cond is switched on. Yeah, not so big deal because most of the time the car is in higher speed cruise. The unit have become to 'extinction', very difficult to get a new one. A friend of mine is selling his used unit of Solex Cisac carburetor of same specification. I bought it and swapped the idle air compensator unit!

NEW on left, OLD on right

 

Note the location of the unit. There are one vacuum line fitted with 2 torx mounting screws. Detached the old unit and swap in new unit, very simple. For me I need to adjust the compensator screw to move the 'handle' further in before it could throttle up. Once installed, you need to start the engine to its operating temperature, turn on the air-cond. Observe that when air-cond compressor is engaged, the compensator 'handle' must move in. To adjust the movement so that it meets same idle rpm, you have to turn an adjustment screw located at the back of the unit. Turn counter clockwise to move in the 'handle' and vice versa until desired rpm achieved. Mine is set around 900rpm.

to move-in the 'handle'

turn counter clockwise