85 305 problems

[Buddy]

I am so mad and PO right now I cant figure this truck out. I have a problem getting it started when i do it burns super rich. The truck runs at high idle around 2000 and when it warms up drops down to 1200. I have listened to everybody around my neck of the woods and all i have relaized is there is a ton of people who think they know what they talking about and don't. I am no mechcanic but this is what i know. the timing is off somewhat and I cant seem to get it dailed in, I know my vacum advance is working and holding vacum, I pulled my plugs and they are as black as if I am running a two stroke. When I shift the truck it feels like it is going to launch through the garage door. ( I think that is because of the high idle) I am running a quadrajet carb I was told it was a rebuild. I also notice that when I kick it down my 4 bbl dont open. my idle screw on the side of my carb doesnt even touch the metal peice that is on the linkage when it is turned all the way in, so my idle screw on the side is pretty much useless. I also noticed that the choke is not hooked up, not sure if that matters. I do know that this thing started great before i tore into the truck, I have done nothing to the motor, just bought the truck pulled the motor and start all the fab work, that was almost a year ago. all that went great with a ton of help from you guys. Thanks for that.   I am so confused now i dont know where to start or what to do. I have tried getting some one to stop by and take a look but all the shops just tell me to bring it in, That is not an option as towing it from where i live is out of the question as it is still in the project phase and no where ready for the road. I have to  walk away from this project right now as it is really getting to me, does this ever happe to you guys?

[Canadian 4X4]

Everyone gets annoyed with a project once in a while. By the sounds of it you have a carb problem and you know you do. I would start there. Some one with more experience will chime in. I would remove it and clean it up the best you can and get the choke hooked back up.

[1979C20]

It sounds like you throttle linkage is sticking, or maybe you return springs are stretched out. Next time you start it up, turn the throttle linkage counter clickwise with your hand, and keep pressure on it, then adjust the idle screw. If the rpms come down, its probably your return springs.

[Buddy]

Ok things afre starting to turn around. I have found a guy that owes a buddy a favor. he is supposed to know his stuff when it comes to carbs and old motors. he is a mechanic and an old stock car racer. he going to stop by the house on Sunday. he tells me he can fix it.....heres to hoping he right

[beastie_3]

Does the carb look like its rebuilt? It could still be a poor rebuild. Qjet?

[Buddy]

it does look somewhat re built, but to tell you the truth when it comes to this carb stuff i am lost. Tuning that stuff from what I can tell is best left to someone who knows what they are talking about, and I know that sure not me. this guy says he can do a rebuild if need be, but he  is the only one that won't give any advice until he has a look.

[beastie_3]

What carb is it? If you plan on keeping it ( if its a quadrajet, Id keep it) get a book to work on it. They are great carbs.

[Buddy]

I will be keeping it, one thing that seems to be a constant on this is to keep the quadrajet so thats what i be doing.

[Grim 82]

If the throttle isn't resting on the idle speed screw then the throttle is probably binding at the choke linkage on the opposite side of the carb. If your idle mixture screws are accessable it's real easy to lean out the fuel mixture with the screws. If you lean it out and it's still dumping fuel like that it needs some internal help. I had a bad "rebuild" once that did pretty much exactly what you describe. I'm using a Holley until I get around to learning to rebuild the q-jet myself.
You won't be able to do much diagnosing on it until you get the idle to come down. Mess around with the linkage until you get it to return to the idle speed screw, get your choke hooked up and check for vacuum leaks and go from there.
Hopefully that guy can help you out.

[runt90]

Are the secondarys sticking open some?  I had this problem before with a q-jet. It will make it idle high and won't work properly when at wot.  I hope this helps some.

[Buddy]

I had a guy come by on Saturday and my my did this guy know his stuff. Took my carb off and rebuilt the entire thing. Made it look like a cake walk. The truck has never sounded so good and it runs like a top. He said everything that could be wrong on the carb was. He said it was a rebuild but not by anyone that knew what they where talking about......ha ha and am I ever happy now!!!!

[Grim 82]

Awesome, glad you got it squared away.

[bake74]

     Doesn't it feel good  to get past your frustration and get it to work right, now you can enjoy your truck.