This is the base plug as fitted to the bottom of (non-remote type) alloy floatchambers on Amal TT and RN carburettors. CNC manufactured in stainless steel. Comes with correct imperial red fibre washer
This distinctive shouldered base plug was of the type fitted to the Amal TT and RN (non-remote type) floatchambers from the late 1930's through to the end of Amal TT carb production. It is worth noting the very early Amal TT non-remote floatchamber (i.e. early - to mid 1930s) was fitted with a different (non-shouldered) base plug, which we also sell - Item 0848, so if you are not sure what type yours is - check the photographs in this and the 0848 item listing.
The purpose of this base plug was to allow for the cross-drilling of the petrol delivery from float chamber to carb in manufacture - therefore as this is to fit a racing carburettor - its thread diameter is larger than the early TT and Amal 276 type base plug's, as the petrol bore hole is a larger diameter than other float chamber types. Note, we also sell the road going Amal 276 type base plug - Item 0847.
Unlike the other two floatchamber base plug types, this version was originally manufactured with a lip, to ensure a good seat on the floatchamber casting - this item is an exact copy, an original base plug having being used as a pattern. It is CNC machined in stainless steel, with the hex being milled as per original imperial hex dimension. It comes complete with correct dimension imperial red fibre washer, which sits flush with the shoulder.
Final point - although only a small component, these base plugs appear in a very visible position close to the timing side of most engines, and originals are nearly always corroded or chewed (they rarely need to be removed, and are normally locked up if you try to take them out). Therefore, I have found replacing the original corroded item with this very pretty version can make a bigger cosmetic difference than would have been expected