bbs or bbd?

[Valcuda]

Without actually taking my carburettor off, how can I tell if my carburettor is a BBS or BBD? The tag got lost decades ago.

[Dave999]

stuff about small Carter carbs

BBS ball and ball single
BBD ball and ball dual

so if you look down the carb and see two holes at the bottom is a dual throat carb made to a design created orginally about 50 years previous, by Mr Ball and Mr Ball. Its a BBD
if there is only 1hole its a BBS, Carter went into an agreement/contract with them (B and B) in the US ( ripped them off) and made their design.
The same carb was also made under licence by EMAIL in Australia and a company that adopted the name Ball and Ball for their version true to the designers name in SA.

2 versions of the BBD (there is also a big carter 2 barrel but i don't know what its called) so maybe 3 versions, but i'll stick with the 2 common to i6 and small v8 on mopars and jeeps

2 versions
high top, early version with an cast alloy top to the bowl and a later version that gets called a tin top, as per the image below
the high top early one, has the accelerator pump through the top cover of the float bowl its flat rod sticks straight upwards. and it is actuated by a linkage on the side of the air horn. should have a metal disk and a clip to act as bowl vent control around the flat rod.
this is the early style carb. 1960s to about 1972

the other has a tin top, a pressed steel plate bolted over the bowl and the accelerator pump rod is enclosed under the pressed square section it is triggerd by a shaft that goes into the side of the float bowl
1972 until they stopped putting them on jeeps in the early 90s

both work

the later carb works better with drop base air claners the bowl top is lower and all that accelerator pump gubbins is enclosed and doesn't get in the way.

if you get a new one its always easier if you just swap the jets rods and springs from your old one in to start with as a benchmark....

the names are usually simple carter AFB = Aluminium 4 barrel
AVS Air Vane secondary (both made by magnetti marelli in spain for edelbrock)



thermoquad like an AVS but has a plastic body and 4 barrels thermo because plastic kept the fuel cool and quad becuase of 4 barrels

etc

BBDs are made in china now look up a seller called SherryBerg and find brand new carter BBDs for $150 sherryberg mopar 318 carb.
if you buy a new one swap in your rod/jet/spring configuration and use quality gaskets and pipe for the dashpot/choke kicker

https://www.aliexpress.com/item/32743944240.html

as you can see views on what is a high top low top or tin top vary, i may have it back to front maybe the tin top is also the high top...arrrgh, so use visual identification to find your carb.



Dave

[Valcuda]

Thanks for that, Dave. As usual, you are a mine of useful information!!!!