quadrajet question

[bigchevyc30]

i have a 1982 c30 with a 454, turbo 400 stock intake and stock quadrajet carb. so me and some buddies at school noticed my truck is running a little rich on a go go juice cause if i crank it when its hot it will shoot out black smoke and you can just smell the unburnt fuel when its running. my question is how would i tune it

[Fairlane514]

Is it a hard start when hot?  If so, float is too high.  If its mixture screws, then turn them in to lean it out, start at about three turns out from a lll the way in. Use a vacuum gauge on full manifold vacuum to get your highest reading.

[bigchevyc30]

well when its hot it doesnt ruen over so well sometime which i figure is the starter but it doesnt do the whole shabang of turning over and over again. also we dont know where the mixture screws are ive never messed with a quadrajet before the only thing ive touched was a edlebrock 600 performer series. is there any way of describing or getting a pic of where the mixture screw is

[Fairlane514]

Two screws on the front at the base plate. one on the drivers side and one on passenger side. The screws point straight forward towards the cooling fan. Both screws must be the same when you are finished turning them.

If the motor grunts when hot when you try to start it, sounds like you have too much advance timing in it. Use a timing light to see where your initial timing is. You will need to unplug the vacuum advance from the distributor and plug it while checking your timing.  Stay around 8-10 degrees for your initial. 

[Irish_Alley]

x2 does sound like its a little advanced

[bigchevyc30]

well idk what carb this is but all i know is it smells of unburnt fuel at the rear of my truck heres some pics of the truck and what the carb looks like also in the one pic what is the thing im pointing to cause it looks like something is suppose to be there but theres nothing unplugged on the truck thanks in advance

[Fairlane514]

That is a quadrajet, if you look at your third picture its stamped on the side.  Im not sure what the port is on the carb, but if it has vacuum either at idle or revved up a little you need to plug it.

On the side where its stamped Quadrajet just behind it there is a stamped number running vertically. You can buy a rebuild kit by referring to that number.

[bd]

You're pointing to the bowl vent that should plumb to the vapor canister.

[bigchevyc30]

If that is for a vapor canister then it should have been plugged from factory cause my truck never had anything for emissions