Hooked up my AC now its Idleing at 1200

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So I threw a belt and a charge on my 60 to see if the AC worked and to my shock it does!!!!!! I was/am super excited being its my first car with AC in over 3 years....now comes the fun part. With the AC off it is idleing at like 1200 RPMs instead of the 800 it was before. I think whatever tells it to high idle with the AC on is stuck maybe? Where should I look first? I was gonna just turn the idle screw down but decided to find the true problem and fix it if its economical to do so....also when I choked it to fire it up this morning instead of choking it just started and went to like 2600 rpms before I could push the choke in.
 
A/C idle up is a vacuum diaphragm attached to the front of the carb. The linkage on the diaphram attaches to the primarly throttle shaft, and you should see an ac idle up adjustment screw.

First, determine if the diaphragm is pulled in, with the engine running but the AC off. If yes, then disconnect the vacuum line and see if the diaphragm releases and the idle returns to normal. If yes, follow the vacuum line to the left inner fender, where it will attach to a vacuum switch. This switch should be stuck open.

If it's not the switch, then check for a stuck diaphragm or sticky throttle shaft. Otherwise you might have a vacuum leak causing the idle to increase.
 
A/C idle up is a vacuum diaphragm attached to the front of the carb. The linkage on the diaphram attaches to the primarly throttle shaft, and you should see an ac idle up adjustment screw.

First, determine if the diaphragm is pulled in, with the engine running but the AC off. If yes, then disconnect the vacuum line and see if the diaphragm releases and the idle returns to normal. If yes, follow the vacuum line to the left inner fender, where it will attach to a vacuum switch. This switch should be stuck open.

If it's not the switch, then check for a stuck diaphragm or sticky throttle shaft. Otherwise you might have a vacuum leak causing the idle to increase.

You have a picture of the diaphram? I don't think its a vacuum leak since it just started as I hooked up the ac but I can check that also.
 
learn to search. I lifted this picture from this thread: https://forum.ih8mud.com/60-series-wagons/273988-87-fj60-carb-photo-diagram-needed.html. It's the one on the front of the carb with the vacuum nipple on top of the diaphragm
IMG_0196.jpg
 
there is also a electrical switch under the dash that has a small nob on it and it will adjust the idle. is just left of the glove box under the dash.
 
there is also a electrical switch under the dash that has a small nob on it and it will adjust the idle. is just left of the glove box under the dash.

The blue knob on the AC amplifier sets the minimum idle speed at which the ac compressor will turn on. It does not effect the idle speed, just whether or not the compressor will turn on at that idle speed.
 
The idle solenoid on the fender has a check valve in it. If the vac hoses are hooked up wrong, the AC will raise the idle, then it will not release when AC is off.

To fix, reverse the hoses at the idle solenoid.
:cheers:
 

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