High idle and running rich

My 86 2.0 is running very rich with a high idle. I replaced the plugs, fuel filter, wires , cap , rotor , pcv valve recently ( just letting you know what has been done tune up wise ). The truck had been sitting in a barn for 8+ years before I found it. After performing a tune up and other maintenance items I've begun to put some miles on the ex farmer. It runs very well with good power across the rev range but it idles around 1800-2000 rpm and you can smell raw fuel. I've turned down the spring loaded screw on the throttle stop but the idle is not consistent. Sometimes it will idle normal but rich and other times it will high idle. It still has the Mikuni carb and I know that it has about 10 screws to mess with so I'm here 1st lol. When cold it will start fine but runs rough until you give it a few revs and then clears out and I know there is a way to reset the choke but again I didn't want to start adjusting anything until I got a little direction so I don't compound the problem. Let me know what you think....Ben

Ah sounds like you are a victim of the dreaded Mikuni fiddler. This will depend on if your choke is operational and the butterfly isn't open or snapped shut tight when the engine is cold. If you have either of those conditions you'll need to set your choke...grrr. There are a couple of screws you will need to mess with. My bet is they've all been wound in because it 'did something'. First up, there's a captive spring in an adjuster on the underside of the main throttle linkage. Back that screw off BUT DO NOT TAKE THAT SCREW OUT ALL THE WAY. That captive spring is a disaster to put back in and chances are you won't find it if it drops out. Now back off the throttle stop screw until you can see it isn't touching the the throttle, then attempt to start the engine. If you can get it to start, wind in the throttle stop until you get an acceptable idle, then reset your ignition timing (with all the adjustments out of whack on the carb it will affect the ignition settings). Now for the first screw I mentioned (this is the fast idle screw). With the engine cold started and running, wind in that screw until you get an idle of 1000-1150 rpm. Don't push on the screw while adjusting it as it will fudge the rpms you're trying to set. Once you have achieved that, let it warm up and open the throttle. The rpms should drop back to your first idle rpm setting. If somehow the fiddler has got to the air/fuel needle, wind it in all the way then back it out 1 1/2 to 1 3/4 turns. That should be in the ballpark.

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Hello i I am in need of some major carburetor help. I know the settings are not right. An I’m trying to follow your instructions but just not getting it. Sorry help me!!