Quote Originally Posted by Richard Farrant View Post
You are referring to a specific model of Solex carb, the 35RZFAIPO, there are only a small number of vehicle types use this particular specification and they would have jets to suit as well as a variation on the fixing for the Zero Starter cable.
Vehicles this one was fitted to were;
Bedford MW, OX, OY and QL
Austin 3 ton 6x4
Ford WOA1 and WOT range
there may be others, but not show in in Vocab.

As for the 40RZFAIPO, that was fitted to the Austin K5, Dennis tipper and Albion BY5 and FT11

The letters each denote a feature of the particular carb and some engines will have a different combination of letters to others.

To take an example of 35RZFAIPO
35 denotes choke tube size (this is nothing to do with choke as in starting, it is the venturi so to speak.
R Governor assembly incorporated in throttle tube
Z Dustproof
F Generic term relating to diecast carb.
A Bi-starter
I Downdraught
P Pump accelerating device discharging straight into choke tube
O Zero Starter

You questioned Zero Starter, this is a device on the side of the carb with a disc valve in it operated by what you might call the cold starter cable ('choke'). It works with closed throttle.
wow, thanks Richard - that answers a whole load of questions