I put a weber 38 on my 86 pickup about a week ago. I have been trying to tune the thing ever since with no luck. I did everything the paperwork that came with it said to do. I tried to set the mixture but i can get it to die out one way but turning it the other never changes and eventually i run out of screw. I tried to mess with the idle but no matter what way or how much i turn the dang thing nothing changes. I put a fuel regulator on and i've run it on all the settings, nothing changes. When i drive the truck the idle jumps to over 2 grand. I dont know to much about carbs but this thing is driving me crazy. Any help would be grately appreciated. Thanks in advance.

 

looks like im on my own

 

i just ordered a 38 for my 87. from what i can see there are 2 mixture screws have you adjusted both? another thing as far as the high idle could be the choke but if it only does it when you drive it, it makes me think the linkage isn't closing all the way, i had this problem with my 32/36. and as far as the idle speed screw for baseline i screw it out then back in till it just barely touches the rest. you could try that for a baseline instead of the half turn in like it says. make sure you have everything plugged off. you should only have one vacuum line going to the distributor. good luck, i hope i don't have any issues with mine.

 

make sure your throttle is shutting all the way. I had to put an extra return spring on my 32/36. Also make sure you don't have a vacuum leak anywhere, inluding the base gasket for the carb. Be patient with the help on the webers not too many of us are using them here. Not too many carb guys either for that matter. And I am still new to the weber, just mentioning my experience with it so far for the past month or so.