I have an 85 Brat that I just put a new weber carb on. Problem is when I got the carb mounted up and started it the car immediately went to 5K RPMs and sat there. I checked the throttle wheel and it was ok. I even started the car with the throttle wheel assembly completely unattached from the carb, but it still idles at 5K RPMs. I know I must be missing something. My guess is a vacuum hose. So far all I have hooked up to the new carb is the fuel line and the vacuum hose to the distributor. My questions are what else do I need hooked up to the carb? And if I do need something else where is it and where do I plug it up. I'm new at this so any pictures, diagrams or whatever would be much appreciated. I can add some pictures tomorrow of the car tomorrow afternoon if anybody thinks it'll help. Thanks!

Do you have your return line still hooked up? Should be on the fuel filter under the hood in front of driver's side. You may need a fuel regulator to reduce pressure going to the Weber. I think mine is set for around 2.5 lbs. fuel pressure. I think all I have is the vacuum line from distributor, wire to chock and fuel line along with throttle cable of course hooked to mine. All other vacuum lines capped or removed. 

Edited July 29, 20178 yr by bratman2

Ok thanks. I did cap the return line. How do you wire up the electric choke?

Wire up choke using the old electric choke wire, it just needs a 12v switched power. Did you set idle stop screw? What are your idle jets? It sounds like the throttle stop is screwed in all the way, keeping it revved up.

On the linkage just inside of the throttle wheel are 2 items of interest.

 

1 is the choke rod. It connects to a lever behind the actual choke. If that lever is tight then the choke is probably set. Push down on the top flaps of the carb and wiggle the lever and you should feel it resease and go loose.

 

2 is the speed adjustment screw. Back it all the way off till it's not touching the lever. The car should turn over and pop a bit but will not start like this. Turn the screw in till it touches then go another half turn or so. Keep going quarter turns until the car starts and idles ok.

 

Dont worry about it running great, just get it running and let it warm up fully so you can run the tuning proceedure, which is an easy google find