I have a 1985 CJ-7 with the 2.5 engine. From 1984 to 1986 AMC used its own 150 cubic inch engine.
This engine differs from the 151 cubic inch GM "iron duke" engine that was in the Jeeps up thru 1983.
I don't ever recall the AMC version refered to as a Hurricane.
As others have said, if its the original carb, its a Carter YFA. These are actually very easy
carbs to get running good, and are easy to adjust, and run quite well.
The air/fuel screw is actually only an idle mixture screw. It adjusts the air fuel mixture
at idle only, and anything off idle is controlled by the computer controlled items
hooked to the carb.
If the carb was never rebuilt, then the idle mixture screw will be hidden under a plug
in the base of the carb. That's probably why you can't find it.
If you are standing in front of the Jeep, facing the engine, the idle mixture screw will
be on the left side, close to the front of the base of the carb.
There should be a plug about .375 inches in diameter over the hole where the screw is
located. If the plug has been removed, look for this hole. If its stil there, you will have to pry
the plug out using a pick or sharp screw driver. The plugs are usually soft metal, and are easily
removed. The actual screw is recessed in the base of the carb about a half inch or so.
The adjustments you make with this screw will only affect the engine at idle, so don't
expect to get the Jeep to run any more rich or lean or run smoother while your driving
by adjusting it. That's not what its for.
If you have a vacuum gauge, you can hook it up to a manifold vacuum source, and adjust
the screw until you get the highest amount of vacuum.
If you don't have a vacuum gauge, then adjust the screw out until the engine starts to
sputter and run bad. Then start turning the screw in. The engine will start to run better
and then start to sputter and run bad again. Count the number of turns you made to the
screw to do this.
You want to then turn the screw out again, but turn it half the number of turns so that the
screw is now at the mid point from when it sputtered and ran bad when it was out and where
it sputtered and ran bad when it was in.
This is about the best you can do to set it without a vacuum gauge.
What I do is I have a flat blade screw driver tip on a socket that I put 4 marks, equally spaced around
the outside base of the socket part. I make the marks about half inch long so they are easy to see.
I use these marks to count as I turn the idle mixture screw in and out so I can get the adjustment
On my Jeep, the number of full turns for the engine to sputter and run bad from in to out is about
two full turns plus a quarter turn. So on my marked socket, I count 9 marks passing by as the engine
goes from sputter-to running good-to sputter again.
So for me, I know I am at the best it can get at 4 to 5 marks, which is about one full turn plus
a quarter turn, or right in the middle of the adjustment.
Hope this helps.