1984 CJ7 Idle issue

[bullseye]

I have a 84 stock CJ7 with AMC 258 i6 / 4.2l cu in (AMC 258 i6 / 4.2l L) engine. While coming to a stop or sitting at a red light, the engine stalls on me and it's idling pretty rough. So I have to sit at the red light revving the engine or coming to stop and even at times make a turn.

I'm not an engine guy here, so pardon my lack of vocabulary...

About every 2 weeks I turn 1 of the 3 screws on the carb which causes the engine to rev higher which in turn keeps it from stalling on me. Within a week or 2, it starts stalling again. Below are some pictures of the carb and the screw I am turning.

Here are my questions:

1) For future reference, what is this screw called (I am turning only the SINGLE screw with the spring sheathing vs the 2 with the spring sheathings that are directly next to each other)?

2) Is this the proper thing to be turning?

3) What are the functions of each of these 3 screws?

4) My theory is the spring surrounding the screw has lost its "spring" and the engine vibration is causing it to unscrew.

5) If #3 is correct, is there anything I should know about pulling that screw and putting a new spring around it? I'm thinking along the lines of torque issues of the spring I know nothing of, etc.

6) In the 2nd picture directly in the middle, what is this piston looking part? What's it's function? The screw I am turning pushes against the piston portion.

7) The 2 rusted springs in the last picture are somewhat loose when not engaged. Are these worth replacing?

Any other advice would be highly appreciated.

 

[PaStomper]

The spring you are turning is for the stepper motor ( the plunger looking thing). If you have A/C the plunger would push out to idle up the motor. The screw with no paint that is on the cam with the steps is the cold idle adjustment. When the engine is cold the cam with the steps is pulled up by the choke allowing it to high idle when cold. The one with the paint is your normal idle adjustment ( when the engine is warmed up).This is the one you want to adjust to set your idle higher. Also the big springs are for the throttle cable return and should hook up to were the cable from the pedal is hooked up. Hope this helps some.

 

[PaStomper]

Also in the picture it looks like the cold idle cam is picked up. If the engine wasn't cold when you took the picture you may want to check your choke spring / heater and make sure it is ok. Otherwise your choke may be partially closed which could give you your problem. Also the carb may need to be rebuilt / serviced.

 

[bullseye]

Also in the picture it looks like the cold idle cam is picked up. If the engine wasn't cold when you took the picture you may want to check your choke spring / heater and make sure it is ok. Otherwise your choke may be partially closed which could give you your problem. Also the carb may need to be rebuilt / serviced.

Thank you for your input.

The engine was warm when I took these pics BUT I had pull on the springs and the throttle to try and get better views to take these pics...

The carb was rebuilt last June and there has been < 1000 miles at most put on it since. (I drive it only in the Summer).

Here a few more pics from different angles. I should have posted these b4...

I can EASILY take more pics if you or anyone else needs a different view.

 

[Old Dog]

I would check for a vacume leak. Buy a can of carb cleaner, with the engine running spray some of the cleaner around the base of the carb.
and where the vac. line conect If the rpm's change you have a vac. leak that need to be fixed.