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I just typed about 1,000 words describing the background. During the typing, I took a phone call and when I came back this forum had logged me out and I lost my post. I do not have the heart to do that again. I'm sorry.

I have a 1985 D150 Royal SE with a 318 and a Holley 2bbl 2280.

I have rebuilt the carb and it runs now except it dies after driving when I stop at a stop sign/light or slow down to turn in. It will immediately restart, but I think the idle is too low while in gear. It idles very well and revs well while in park. While cold, before the choke opens, it does not die while stopped in gear.

I think I need to tune the carb and maybe adjust the timing, but I cannot find a good source to do that.

Can someone please provide me with a good set of instructions for tuning/timing this engine and carb?
 

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I'm not sure of the exact year they did it, but I'm thinking it was actually in the late 70's when they made it impossible to adjust those carbs in any way as to tuning. About all you can do is make one change to the accel pump linkage and adjust the idle with the idle adjust screws in the linkage. It's been a while, but I think they had two idle set screws, one for cold running when the choke is involved, and one for warm operation. Sounds like you need to crack open the warm operation screw a bit.
 

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I do have those adjustments that you mentioned, but I also have two mixture screws on the front of the carb. This carb may be older than the truck or maybe on 85s you could still adjust.
 

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You definitely can't adjust the 80's era carbs, so I'd bet it's an early 70's model. Ok, so I'd gently tighten (actually don't tighten, just flush them down) the screws all the way down, then open about 2 full turns. That's a good place to start. You can tweak a quarter turn more or less at a time, 2-2 1/2 turns is going to yield the best idle quality. If you're quick you can do this with the engine running and gauge run quality (bump up the idle screw to give you around 2000 rpm. Wherever the engine runs best is pretty much where you want to set it. If you get no obvious change, you probably have a clogged or damaged idle circuit. Usually, when it's toast, you can adjust one screw and hear changes while adjusting the other does nothing. Then set your idle screws and try it on the road.
 

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will this ajustment work for a truck that runs rough and has a bit of a miss at cold idle. it sounds like he has the same carb i do in my 82. its hard to start when its cold and runs rough till its warmed up a few min. but then it purrs like a kitten no issues on re start.
 

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Hello , I have an 85 D150 and had issues like this, I'm actually still working out the fine tuning because I'm getting a slight hesitation.
The carb I had on there had it's mixture screws blocked or plugged but I eventually bought a new/rebuilt Holley 2 barrel which has mixture screws I can turn.
If you're facing your engine, the mixture screw to your right is the idle, and the one to your left is the air mixture. Shut off your engine and close both screws very gently. Once you feel them stop open them both 11/2 turns and then start your engine and see how it runs, then you can adjust from there.
There are also screws on the back of your carburetor which controls the idle by propping the accelerator back which would be like the same thing as pressing your accelerator down, you may have to adjust that screw to prevent stalling.
You may also want to check all vacuum lines, fuel filter, fuel pump, fuel lines ( I replaced all of mine) and make sure your choke works properly. It should Idol hi from a cold start and then you kick it down and it will run at a low nice idle.
 
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