85 k10 carburetor issues

[85k10-chevy]

85 k10 carburetor issues. New to this need help please

I have a 85 k10 that has a Qjet carburetor thats emmisions an vaccum. Everyone ive talked to said they are nothing but a nightmare an go with a mechanical carb. But i took it off as the plan was to get a kit an rebuild it but said hell with it.

I hooked it back up but it not running right. Idle is stuck way up in rpms. Not the throttle linkages. Just dont know where all the vacuum lines go. An i believe its the pvc or pcv valve not to sure what it is, comes out the top of the drivers side valve cover. Hoes was connected but it broke taking it off.

When i put everything back on i plugged the hoes with my thumb an idle went down so figured that was the problem. Put a bolt in the vaccum line an for some reason idle never went down. But so many vacuum lines going everywhere not sure what's suppose to go where.

So if anyone knows what I'm talking about could you please help me out an if there's any bypasses i can do or diagrams something i would greatly appreciate it.

 

[crpntr78]

Look at the post titled "700r4 vacuum hose" from yesterday. There is a vacuum hose diagram given in the post answer. See if that helps you any.

 

[1987 GMC Jimmy]

I have a 85 k10 that has a Qjet carburetor thats emmisions an vaccum. Everyone ive talked to said they are nothing but a nightmare an go with a mechanical carb. But i took it off as the plan was to get a kit an rebuild it but said hell with it.

I hooked it back up but it not running right. Idle is stuck way up in rpms. Not the throttle linkages. Just dont know where all the vacuum lines go. An i believe its the pvc or pcv valve not to sure what it is, comes out the top of the drivers side valve cover. Hoes was connected but it broke taking it off.

When i put everything back on i plugged the hoes with my thumb an idle went down so figured that was the problem. Put a bolt in the vaccum line an for some reason idle never went down. But so many vacuum lines going everywhere not sure what's suppose to go where.

So if anyone knows what I'm talking about could you please help me out an if there's any bypasses i can do or diagrams something i would greatly appreciate it.

I'll reattach that 1983 diagram. Unless your truck was from California, that should be the correct thing. As far as the super high idle, there are several places that can be coming from. I recommend capping everything and working with just the carburetor. You can buy a little cap kit from O'Reilly's for a few dollars. Make sure the carb bolts are tight, but don't overtorque them. Even then, the base gasket could be bad. Get some starter fluid or spray carb cleaner and spray it around that intake area and see if your idle changes. If it's does, you need to remove the carb, clean both mounting surfaces well, replace the base gasket, and retorque the bolts in a criss-cross pattern. Also make sure no air horn bolts are loose. I suspect this will greatly improve things. If it still persists after that, I'd spray around the carb again to see if your idle changes. If it does still change the idle, the body of the carb maybe warped from improper or overtorquing. If not, the only really massive vacuum leak site is the intake manifold gasket. The Quadrajets are excellent carburetors when hooked up correctly and tuned correctly. I drive the hell out of one, and it's great. The emissions stuff is extensive and much of it can be deleted. Look over that diagram and take inventory to see what you have, and we can figure out what can be kept and what can be deleted, but you gotta get the carb squared away before we can look at other stuff, I think.

 

[85k10-chevy]

If the hose broke for the pcv valve i plugged the hose but havent coverd the last of the pcv vavle coming from the vavle cover would that make a big difference as of a leak to make it idle higher or doest that matter to much

 

[1987 GMC Jimmy]

If the hose broke for the pcv valve i plugged the hose but havent coverd the last of the pcv vavle coming from the vavle cover would that make a big difference as of a leak to make it idle higher or doest that matter to much

The vacuum leak is gonna come from the carb direction, not the valve direction. A single port won't make that much difference, but multiple ports or a big carb base leak will.