Carburetor

[johnnorfolk]

Hi, Does any one know if its possible to date a carburetor?

[MarkO]

Perfectly possible to date a carb - just don't buy her flowers or an expensive meal. The finest E5 will suffice if you want your relationship to flourish.....

Extract below from somewhere - looks like a 276 to me.... is there a stamp on the flange?

Amalgamated carburettors (known as ‘Amal’) began in the 1920s and continued to supply British machines with carbs up until the 1980s. The original Amal carburettors had brass bodies and separate float chambers, and were known as types 4, 5, 6 and 29. They were fitted from 1929 until 1933 when the body material was changed to a zinc die cast alloy. These were known as types 74, 75, 76, and 89, and can be distinguished from the later types because these have four air holes around the base of the body which the next type do not. In 1939 types 274, 275, 276 and 289 were introduced; these have two internal primary air passages in the base of the jet block. A later version with an ‘R’ suffix denotes that the primary air passage hole was moved to the air intake.
1955 saw a completely new carburettor being manufactured that had the float chamber cast in one piece with the mixing chamber, which is why it is called the ‘Monobloc’, these are types 375, 376, and 389.

[Roger Gwynn]

The number will tell you which machine and settings it had originally, largely meaningless as all that can be changed except for the bore size, which is the only bit you need to worry about. The number after the '/' is defines the float chamber, the important bit here is the angle of the dangle. It appears you have the 4 air holes, which would make it the 1933-38 type 74 etc.

[nevhunter]

the Later (of the separate Bowl) types are better suited to having an Air cleaner fitted. Generally Zinc based diemetal is a bit of a disaster. I wouldn't waste a lot of money on one unless the body was NEW . The brass jet block has to match the Body type
In Australia, after market brass bodies were Produced back a while. Nice it you an find one There's a bit of work in a Jet Block. THEY, and the slide can wear. There are semi finished slides around.
By the way, the Concentric is a far better carb than the Monobloc and there are Swedish Amals. The bore size of the carb should be related to the Gas Flow the engine makes for it to be tuned over the whole throttle range. Multi cylinders run smaller carbs as the Flow in more Constant. Less PULSES of the single type. Nev

[johnnorfolk]

Thanks everyone, thats all very helpful. It is indeed a 276 which is a little strange as its on a 1942 WNG, but then its twin port so nothing is ever that strange. Thanks again.