Revs increase when brakes are applied

[jpjeep26uk]

Hi all
My revs have started to go up when I touch the brake pedal or when I stop with the brake and then pull away.
I've read a lot of things but mainly that it's the Brake Booster, probably got an air leak or the diaphragm is busted inside it.

If that's so, then i'll buy an new one and fit it.

But, and here's where I need your help, can it also be related to the Carburettor? I had 32/36 Weber clone put in to replace the EFI.
I've never been able to get it set right and although she runs really well, I have a lot of issues with cold starts, crappy choke mechanism, high idle, normal idle, what have you.
So frequent tweak with a screwdriver has been the only solution.
1. Could playing with the Carb settings affect the brake booster?
2. Anyone out there any good with carbs and can tell my what to do if I send a pic of the carb and point at the bits that I don't understand?
I know how to baseline the carb but within days it needs tweaking and I'm worried I've screwed the brake booster by playing around.

I've played around with this screw as I read it was the choke high idle adjuster???
As usual, any help would be hugely appreciated - thanks.

 

[Gilaguy23]

There is nothing you did or can do with the carb fiddling that damaged your booster. Id suggest disconnecting the booster vac line, plugging the intake and while sitting hit the brake pedal and see if you have the same thing go on. I drove my 73 FJ 40 for while with the booster unhooked because of a massive vac leak. It was not much fun and unsafe as you really have to smash the pedal to get any brake action. The basic idea on idle mix settings is to obtain the highest vac reading when turning the mix screw. Im no Webber expert but remember that single car type webber being a PITA that was OEM on one of my Ducatis. Once warmed up, everything normal,fuel pressure etc, there is no reason to have to be readjusting it all the time.