Carburation

[Geoff Dowdle]

peterg,
What model Bristol are you working on ????
If it is a 403 (AB2 engine as you advised) the bottom of the tank has probably got a lot of corrosion in it and might need replacing .

The fuel lines often get squashed where they go under the chassis , just forward of the LH rear wheel area . Foreign matter can get blocked in this restriction.

If you want to fix the problem properly I suggest you inspect for leaks , remove the tank , initially clean & inspect it internally , if a alloy 401/3 check for corrosion holes , replace the fuel line & filter (I assume you have a proper disposable filter between pump & carbs).

You should then have a clean fuel system to the carbs which will be a good position to then start a correct tune up.

Geoff