Carb tuning help

Ok so I did I divorced choke thermostat install on my 2245 holley carb and when I started rv it started up fine without me adding carb cleaner or gas into the carb it ran fine except the black smoke coming out of tailpipe I looked it up appearly its fuel filter or sencor so I put my filter on and the black smoke started turning white just before I ran out of fuel but with filter on the engine started running at high rpms idk how many but you could hear the high idle I was wondering if I need a chart to tune it and if no what should i be looking to adjust and if so does anyone have a chart that isnt blurry and readable. It’s a 1975 dodge sportsman with a 360 2bbl 2245 holley carb

The choke pull-off is inoperative or improperly adjusted.

Looking at your picture from Oct. 2nd, the choke pull-off is missing from your carburetor, it should connect to the plastic cam on the left side of the carburetor.

You need to adjust the fast idle screw for 1,850 rpm with a warm engine and the screw on the second step of the fast idle cam. I assume this is a 360 engine since that was the one that used the 2245 carb.

I’ll recommend that you read the directions on adjusting the linkage and then operate every sequence of the start up steps to get an understanding of what’s happening.

If the choke is for some reason stuck in the fully closed COLD position then the carburetor will have it’s throttle open to a very high idle while starving for air. It’s much easier to get things right when you understand how things operate.

You ran it out of gas? You need enough gas to be able to do anything. Been a long, long time since I have worked on a carburetor equipped engine, but as I remember you should be able to see the choke open as it warms up, and when you ‘blip’ the throttle it should come off the high idle cam.
So, if this is the first time the engine has been run in a long time the black smoke could be either from running very rich with the choke on or crud in the engine or exhaust system or combination there of.
Then you can figure out the ‘white’ smoke, could just be normal condensing of the exhaust in cold weather.

I agree with the choke pull-off diagnosis but keep in mind as mentioned that there are a number of things that overlap and all must be correct for it to function properly.

I remember back in the day seeing several Quadrajet carbs that had inoperative secondaries.
The cause turned out to be a roll pin in the throttle shafts that dislodged just enough to catch the secondary linkage.

Ok I get what yall are saying and will look into them now when I bought the divorced choke thermostat because mine didnt have one but it had the setup to add it I was doing research on how to do it by watching Mike’s carburetor parts videos and in the video the guy have a chart for doing measurements my question is do I need that chart and if so where can I get one? Oh and I bought they same carb for like 50 bucks on ebay for the conversion setup for my carb that was already on it it’s the same from a to z I made sure before I put the conversion on my carb I already have. And would it be best to buy a rom reader or just Barrow one from like a autozone?

Ok I went back I looked at what Nevada was talking about and I have that choke pull off it came with the carb I bought from ebay and my setup the choke pull off is connected to the arm of the choke I’ll have to look later but pretty sure the only place to install the pull off was on my right side. But to be safe I’ll double cheak

Not sure what you mean by “I did I divorced choke thermostat install” , but a couple years ago I successfully rebuilt an Autolite 2100. Are you able to visually confirm the choke plate is opening to the full-open position as the engine warms? Does the choke plate partially open immediately after the engine starts?

The choke plate isn’t going to open much upon the engine starting until the vacuum operated pull-off is installed.

I can see how that would be the case … lol … is that what OP means by divorced choke install?

No, divorced choke is where the choke thermostat is mounted somewhere other than on the carb, usually a well in the intake manifold. This was typical for Chrysler products with Carter or Holley carbs. GM cars with Rochester carbs had the choke thermostat under a black plastic cover on the side of the carb.

When the engine started getting warmed up I notice that the pull off sucked in and the choke was opened up about a pins distance from the wall before the rv ran out of gas

Again, how can you expect to adjust your carburetor without an adequate fuel supply?

When the engine starts the choke pull off should immediately open the choke to a gap the width of a quarter or more. And when the throttle is pressed open the choke should move open along with the throttle plate.

If you open the choke fully and pin it open and the carburetor and fuel pump are basically operating anywhere near correctly the engine should start when cranked if recently flooded. If not recently flooded pumping the accelerator a few times should enable starting.

If you don’t have a CO2 extinguisher handy already get one before you continue.

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Yeah I have a one ready and ok that’s what I was thinking that it should of popped open instead of staying closed and doesnt move when I pressed gas I’ll have more info when I get paid again to get more gas also i put about 10 gallons of gas in maybe little less but it didnt have that much this time as I had to move it to storage for winter.

Ok so Its been crazy week but heres the setup

Tuesday is when I’ll be able to put more gas in it

Shannon that carburetor has been hacked beyond belief. Here’s what I see so far: two vacuum hoses plugged with screws, one vacuum port near the bottom of the carb connected to nothing, and the rod from the choke thermostat is NOT connected to the choke. I know how much you want to straighten this out yourself, but I fear you are out of your depth, and there is only so much we can do from a distance. You need to find an old mechanic soon, as we’re dying off at a rapid rate :wink:.

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If you can’t afford to put gas in it now what are you doing with the thing in the first place.

It may not be an easy task, but the OP needs to (somehow) find an elderly mechanic, as the younger guys have likely never had to deal with a carburetor, and as a result, those younger mechanics will have no clue regarding the function or the adjustment of a carburetor.