Truck Repair: Truck not starting, scotsdale, air cleaner

Question
I have a 1986 C-10 Scotsdale with a carbureted 4.3 V6. Had some trouble with starting and running soon after it got cold. Took t to a shop and had a tune up done (changed plugs, wires, cap and rotor, and had the fuel/air mix adjusted). It ran fine for about a week or two then the temp dropped to below zero for about a week and now the truck won't start at all. I waited until it got warmer and tried. First it would just turnover as if it wasn't getting any gas. Now it will turn over and act like it wants to start but won't. Any suggestions?

Answer
Hi Dave,
There is a choke that needs to both close properly, and then open properly.
In addition, you need spark.

Check for spark, then remove the air cleaner, hit the gas pedal one time, and see if the choke plate slams shut.

As you crank, it should open just a little.
If you hold the gas pedal to the floor, the plate should open a lot.

Of course, after it starts and runs for a while, it should open all the way, but we need to get it started first.

Any water in the gas?

Have you looked inside the carb throat as the gas pedal is pressed, to see if a good healthy shot of gas sprays into each throat?

Do all that.

Van