Bristol 400, 1950 question about a button

[Rombrand]

Dear all,
I have just bought a nice fantastic Bristol 400.
My question is about the button "CARB". Can someone explain what that button is about and how to use it.
Thanks Roman

[Hydroglen]

Push or pull the button...then turn the key and perhaps pull the choke. Motor will start and you will then turn the switch off.
It powers a solenoid that feed fuel to the manifold. Will NOT work if you try to operate it with the key on first!

Dorien

[Geoff Dowdle]

Roman ,
Congratulations on your purchase. What carburettors are fitted to the engine ?? Solex or SU

The Carb button is a switch to a Solenoid which activates an enrichment device incorporated with the float chamber of the front SU carburettor only .
It will only work if the ignition is on .
There is also a Mixture button which operates a pull cable to a lever on the centre SU carb .
The rear carb has no enrichment /coke device fitted.

In cold weather from a cold start you usually have to activate both buttons , if it starts without it indicates the carbs are set way too rich.

If three Solex cabs are fitted the Carb button is not used , only the Mixture cable .


Could you please advise the chassis and registered number of the 400 and post a few photos on the Forum or direct to me to update the 400 Register

Thanks
Geoff Dowdle
BOC Joint 400 Registrar

[Rombrand]

Ho Dorien,
thanks for the explanation. A last question regards the button if you do not mind. What is the purpose of the button and when should it be used?
Thanks and have a great day!
Best regards,
Roman

[Rombrand]

Goeff,
thanks for the feedback. I will post some pictures in the next days. Best regards Roman

[Rombrand]

Geoff,
so in other words, if it is a Solex Carburettor the button CARB does not have a function, it only works with a SU carburettor?
Best regards,
Roman