February 7 saw the club meet at Ken Parker's shop in Van for a session on carburetors. Several of us brought our own to work on. Ken spent the morning walking us through the process of disassembly and evaluation of the various parts to a carb, cleaning and then reassembly.
(Here is a good diagram of how the Model A carb works.)
A very important part of making an 'A' run properly is getting all of the jets properly sized so that they flow gasoline at the proper rate. According to Ken, a jet is measured by using a constant 3' water column, and then measuring the flow of water through the jet for a minute. Ken had his apparatus set up, and all of us took the opportunity to test the jets that we had in our carburetors. (Sorry, I don't have a picture of the test rig, maybe someone else can supply one.) Ken showed us how a jet that is not flowing the proper amount can be fixed, either by very slightly drilling out the hole, or soldering the hole shut and re-drilling a smaller hole. But you have to have a set of small drills: a set for sizes #61-#80 is available at most tool-supply houses. (Do a Google search on "drill index 61-80" for a wide selection.)
Another important part is making sure the passages in the carb are clean and will allow gas to flow. A small light is helpful. Ken was using a small LED light but suggested the fiber optic adapter for a MiniMagLite (See here.)
After, I did a bit of 'net searching and came across this site:
Ken showed us a paper worksheet (all 17 pages!) that he has found useful when overhauling a carburetor. It used to be available from the above site but seems to have been lost. I have asked the Model-A.org folks for permission to reproduce the document, and if/when I do, it will be on our website.
And, once again, our better-halves came through! Lillian cooked up her famous gumbo with chicken and shrimp and sausage and .... makes my mouth water just thinking about it! And several of the other wives brought desserts to go along.
Thanks Ken and Lillian for hosting this tech session!