Choke adjustment?

[digimurda]

Ok, I think I figured out the cold start thing, seems to crank right up now,
But now it wont drop even after 4 or 5 minutes no matter how much I tap the gas,
Stays idled on hi too long, drops a little but not enough after 4-5 minutes

 

[Bonnewagon]

Eyeball the choke side and see if the green tang is dropping down. That is what releases the choke. When the car is cold, and you step on the gas pedal, the spring in the coil closes the choke butterfly, and actuates the fast idle linkage, of which the green tang holds the fast idle cam in the "fast" position. It is weighted so it falls down and releases the fast idle after the car warms up. Check for dirt, clean with carb cleaner in a can, and check the hot air pipes that go from the manifold to the choke housing. The pipes should be clear and any blockage will make it take a long time for the coil in the choke housing to get hot, expand, and release the choke. There is a vacuum passageway in the carb that passes into the choke coil housing, drawing hot air from the pipes in the intake manifold exhaust crossover, heating the coil spring, releasing the fast idle. Look there for your problem, making sure the pipes are clear.

 

[digimurda]

Eyeball the choke side and see if the green tang is dropping down. That is what releases the choke. When the car is cold, and you step on the gas pedal, the spring in the coil closes the choke butterfly, and actuates the fast idle linkage, of which the green tang holds the fast idle cam in the "fast" position. It is weighted so it falls down and releases the fast idle after the car warms up. Check for dirt, clean with carb cleaner in a can, and check the hot air pipes that go from the manifold to the choke housing. The pipes should be clear and any blockage will make it take a long time for the coil in the choke housing to get hot, expand, and release the choke. There is a vacuum passageway in the carb that passes into the choke coil housing, drawing hot air from the pipes in the intake manifold exhaust crossover, heating the coil spring, releasing the fast idle. Look there for your problem, making sure the pipes are clear.

will do this this afternoon, can it also be the choke pull off?

 

[Bonnewagon]

The choke pull off operates as soon as the motor starts, it is vacuum operated. See Tobyp's second picture. It shows how it opens the flap a bit so the motor won't stall. It doesn't affect the fast idle or curb idle. But if it is not adjusted right the motor will run crappy until the choke opens all the way. If the motor stalls right away, it's open too much. If it chugs and smokes, it's too far open. In the older carb specs there is a measurement for the opening, easy to check with a drill bit. After 81' or so they went to a spec for the angle of the flap, a very difficult thing to measure without the specific GM tool. I just go by the old measurements.