Re: Carburetor Question Carter WA-1

Posted by HH56 On 2018/7/4 15:20:35

Is there an opening in the top of the exhaust manifold a short distance in front or back of the port on the carb choke housing? If so that is the choke stove and where a piece of steel or copper tubing connecting to the choke housing lands. Generally the end of the steel or copper tube is just pushed in as a snug fit in the choke stove tube. Some manifolds have a square plate covering a box like chamber cast into the manifold which works as the stove. Believe the tubing screws onto a fitting in the plate with that arrangement.

The tube type stove consists of a steel tube which is pressed in holes in the manifold and has an opening on the bottom which lets some air in. The steel tube just passes thru the manifold and at no point is the exhaust gas and the air in the stove tube able to mix. The chamber type uses the same principle except the manifold casting acts as the stove and metered air is admitted thru a small hole the chamber cover plate. Vacuum from the choke system draws air from the stove which has been heated by the exhaust gas in the manifold so it can work the bimetal element in the choke mechanism. As the element heats it relaxes so the choke can open. When the choke opens the vacuum is reduced so there is just a minimal amount of heated air present to keep the element relaxed.

There is a photo of a six engine in the 39 archive which may show the tube. Since the photo is not the best and is taken from a distance I can't really tell for sure if it is the tube or linkage so won't post unless no one else has anything better.