Cousin Robert has lent me the Green Family tools for adjusting English car carburetors. He recently sold his Triumph TR6 and though I might need 
the tools. He was correct.
The two instruments to the right measure airflow into a carburetor. Why is this important in a Sunbeam? Like Robert’s TR6 and my Corvair, most Sunbeams have two carburetors, and for them to run well, the carburetors need to have roughly the same amount of air passing through them.
For the Corvair, we made a balance tool from a piece of lumber, about six feet of clear tubing, and some hydraulic jack oil. Because each if the Corvair’s carburetors had its own vacuum port, we balanced 
the flow by measuring relative vacuum. In the picture just to the right, you can see that the tubing is looped into a “U” on the board. With the engine running and both ends of the tube connected to vacuum ports, the carburetors are balanced when the oil is at the same level on each side of the loop. A careful viewer will see our 1994 Volvo 940 in the garage. Aaron and HannaH drove it until 2014. It was a wonderful car.
Unfortunately, the looped tube tool cannot be used on a Sunbeam because only the inner carburetor has a vacuum port. Even if
A beardless Daniel works on the Corvair. Nice sandals.
both had ports, I believe both carburetors are connected to a common intake manifold and therefore are likely to have the same vacuum.
Back to the Sunbeam. The idea is to place one of the tools above on each carburetor air intake (after removing the filters) and then adjust the idle speed screw to equalize the readings on each carburetor. We tried both and ended up using the device on the left because the needle is easier to see.
We used the Workshop Manual–a 400 page book that came with the Sunbeam– to make the adjustments. Each carburetor has two: idle speed and air-fuel mixture. The picture on the left shows both carburetors connected in the middle to the fuel line. On the right is a view down the carburetor’s air intake. The screwdriver is lifting up the air piston, which modulates the amount of fuel entering the engine. If you look carefully, you can see a needle-like pin in the center. This is part of the fuel valve.
The general idea is to preset the mixture by closing the adjustment a set number of turns and then use the balance tools to set the idle.
Following the manual as closely as we could, the car ran better, but not perfectly. We then tried a third tool from Robert, the Colortune, pictured above. Robert said that it was hard to use and he was able to make use of it only once. We decided to try.
Sunbeam 