I wasn't able to register on the classic truck forum so figured I would try this question here. I have a 73 Scout 2. It had been sitting for a while when I bought it a few years ago. I redid the carb to get it running. It ran but flooded. A more knowledgeable mechanic adjusted it properly to specs. Now, it idles fast when started. After it warms up, it idles low, then stalls unless I keep my foot a little on the gas. After it stalls, it won't start unless it sits for an hour or more (roughly), or it will start when warm if a little gas is put in the carb. Suggestions ?
 
You need to re do the carb. Sounds like the float is low or sticking and may need the idle jet adjusted. Is it a holley 2 barrel.
 
Carb problems.

The too fast idle when cold is a simple adjustment. If it's auto choke, there will be a fast idle cam that has an adjustment screw. Back it off to the proper fast idle. There is also a choke pull off diaphragm, a vacuum actuated device that slightly opens the choke when the engine starts. It can be inside the black choke cover, or under the air cleaner, depending on the carb model.

If it's manual choke, find the fast idle adjustment and back it off.

Then there is a warm idle adjustment. It will be an idle speed adjustment against a fixed stop that sets the main idle speed.

There are also idle mixture screws. Turn each in slowly until it runs rough, then back out to smooth, then 1/8 to 1/4 more. Try to get both the same.

The stalling and not starting could be the accelerator pump not working. Looking down inside the carb, engine off, you should see a 2 streams of fuel squirt each time the throttle is operated. It must begin to squirt the same instant the throttle is beginning to open. There is an external linkage adjustment to an arm that operates the pump diaphragm on the front of the carb.

Those carbs (either a Holley or Autolite) were prone to leak fuel both internally through the power valve, and externally through the accelerator pump diaphragm. If it's a Holley they leak around the bowl gasket, especially if it has been sitting.

Internal leakage will show as rich running, black smoke, and excessive cranking when cold from the the bowl being empty, and hard warm start from flooding.

Keep a close watch! They are a fire hazard!
 
You still have a crab issue. Unfortunately they haven't taught carbs in school for some time, a long time. So basically you have to find an old mechanic or a young guy who loves older stuff.

So your options are to find the right guy or convert it to fuel injection.

Rick
 
You also didn't say whether it was a 6 or a V8. The sixes were AMC, and they used either a Carter YF single barrel or a Carter BBD 2-barrel. The IH V8's used a Holley 2-barrel.
 

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