This is slightly O/T since it has to do with my parts truck, but I have all my books packed up and can't find any help on the internet. Here's what I'm working with: '72 460 with a autolite 4300 4bbl. I rebuilt it, everything seems to move free and be in the right place. I put a manual choke on it. I can only get it started with the choke shut, even when it is warm. It will start on the first rev. this way. Once it starts I have to quickly open the choke so it doesn't die. with it open all the way it has good response. Only way I can drive it is have the choke 1/2 open and it runs like crap, but it will start. This carb has both an fast idle speed screw and a fast idle cam screw. Any suggestions? I'll put the auto choke back on once I can get it to start without having to close the choke everytime.
I guess I'd look somewhere other than the fast idle adjustment first. Unless of course the fast idle is a problem. if it won't run down the highway without the choke pulled part way it sounds like a different problem. Down the highway you're off the idle circuit all together aren't you? Sounds like its trying to starve itself. I could be wrong (wouldn't be the first time ) Are you sure that the floats aren't a little low? Are you sure that you don't have a vacumm leak somewhere? Not much help I guess. That's where I'd start looking.
I tried looking for vaccum leaks, cause it seemed to be a logical answer. I took off every hose one by one and plugged the port while it was running. They didn't make much of a difference. I tried the carb cleaner trick, but it took so much to bog it down it was useless. I think I'll pull the carb off tomorrow and re-adjust everything. Anyone have the specs? I lost it. What's a good starting point for the mixture screws? they are a bitch to get to while it is on the truck.
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