I just recieved a quadrajet that I bought from a guy online. I got the carb fully mounted on the car and was hooking up everything and then when I went to start to hook up the cables I notice that there was only 2 spots instead of 3 to hook them. The kickdown cable spot was missing. I dont know if it was factory like this or not. It is still on the car but it appears almost like the spot on the bracket where the kickdown cable would attach has been cut off. I still have my old one so I have the bracket but really wasnt looking forward to taking the base appart. I looked at it and it might not be that hard, but last time I tried to unscrew the screws that held the throttle blades in a quadrajet all of the screws broke off. Does anyone have any suggestions or proper procedures to follow changing this. I would have already started working on it but I couldnt find my torx bits to take the base off.

Ben

 

Momar,

Start soaking the base of your old Rochester. You may need to swap that throttle shaft. If you have access to a TIG welder, you could grind off the staked end of the throttle shaft that holds the bellcrank from the old carb, grind off the same end from the replacement carb, fit the good piece, and weld it in place. You could also have a "flag" of material welded, brazed, or silver soldered onto the existing bellcrank, drill the hole you need in the correct location, then connect the cable pivot.

If you want to retain the factory staking of the belcrank to the throttle shaft, you'll have to change the throttle shaft and carefully realign the throttle plates.

Or, take an old Holley 4160 off my hands.

I'm a little confused as to why you didn't just rebuild the old Rochester in the first place. Was there some breakage or mechanical damage to it?

 

Well, my old one had excessive play in the throttle shaft. I did an attempt at rebuilding it before I knew this and it ran but not real well(this was my first time trying this) I didnt want to mess up this motor by not getting it broke in right because I messed something up in the fuel mixture. As far as the trottle shaft is it the shaft or the carb base that wears? What lining up do I have to do on the throttle shafts? Dont they just screw on? By the way just out of curiosity how many cfm is that carb and what do you want for it?

Ben

 

Throttle shaft play is usually due to wear in the throttle body, not the shaft. The throttle plate alignment is crucial to allow the throttles to close fully and evenly without binding. You'll probably have to adjust them several times to get them right, but it's worth the effort.

 

Well, I dont have access to any parts soak, so I tried soaking it in carb cleaner for a while. The screws still break off. I broke off 2 of them in my old carb and stoped. Does anyone know if I could buy a new throttle shaft? I could get the throttle shaft out if I drilled the screws out, but I dont know that I would want to use tap the throttle shaft and worry about not geting something not quite right. Thanks for the help so far.

Ben

 

the plastic bushings fall out of the shafts.you cant find another carb base plate?

 

I dont have access to another base plate no.

Ben

 

do you realize that the baseplte will work off of alot of gm cars/trucks with the same cu.in. motor?

 

Yes, but I dont have any others. That is the reason I bought this carb is because the base on my other was screwed.

Ben

 

so now your double screwd?

 

Is it a computer controlled Q-jet? That carb you bought might
be from something like a C-50 truck with a manual tranny

 

Well, as far as how screwed it was, a friend of mine had one of his instructors look at it and he was suprised it ran very well at all on the 305 because of the throttle shaft play. He said it would need some kind of bushing pressed in. The one I got doesnt really have any noticable throttle shaft play, but it is missing the bracket(looks like it was cut off actually). I was going to try to put the other throttle shaft in if it looked good when I pulled it out but it broke 2 screws. I bought some B12 carb cleaner that came in cans and have the old base soaking in that(since yesterday evening) and am going to try to take the other 2 screws out and see if they break. If they dont I will probably try to use screw extractors or something to get the others out. Oh, and the guy said it came off of an 85 IROC. It has all of the same vacuum conections as my 85 also.

Ben

 

How close to the actual shaft was the leg cut off? If it still has a little "meat" left, you could cut your arm off longer and fasten it on to the new carb with a couple of screws. A bit hokie, perhaps, but it should work.

The throttle blade screws are swaged after installation to prevent them from backing out. The only proper way to remove them is to Dremel the threaded end flush with the throttle shaft chamfer, then back them out from the head end. This requires new screws for reinstallation.

 

Well, that figures. Do you know where I would get new screws like that? Also, I there is not much left to attach to with screws. It actually is cut up to about mid throttleshaft and then goes down and around it and back up and levels off again. As far as getting the 2 broken ones out what would you suggest? Do you think it would be possible to use a small drill bit in it and use it to turn it out the bottom?

Ben

 

You could try the drill bit into the broken off screws. If not imbedded too much from the attempt to remove against the swaging, it might work.

Carbs Unlimited may be able to help you out with new screws, or perhaps even the entire throttle shaft. 1-800-994-2272.

 

Well, I just talked to them on the phone and they said that they do have the screws but no throttle shaft. Also I checked and I dont have any drill bits that small. I am going to see if walmart has some cheap ones. Man, all I need is that throttle shaft and the car should be ready to run. This is kind of agitating. If I cant get those 2 screws out I will probably have to go junkyard hunting and last I checked the junk yard only had one thirdgen still and it had a torqer II intake and holley carb but they werent selling parts off of it yet.

Ben

 

Ok, I've about ****ing had it with this thing. I tried to break one of the secondary srews like happened on the primaries so that I could test drilling one out. Every ****ing one of them came out fine. So, I tried to take of as much of the bottoms of the primary screws as possible without tearing up the shaft and the tried to take them out. They both broke. I tried to drill one and see if it would screw out the bottom and it just kept sliding off no matter how fast or slow I drilled and I broke 3 bits trying to do this. I just payed 50 bucks for this carb that I cant even use because I dont have a throttle shaft to put in it that has the kickdown cable on it. I cant afford much right now and thats why I bought a carb from someone instead of sending mine off to be rebuilt and have bushings pressed on for the throttle shaft. If anyone happens to have a good extra base for a cc quadrajet that they would sell me fairly cheap please let me know.

Ben

 

You don't need a thirdgen carb. I saw a carb like what you need in my storage yesterday. And I know I have CC Q-jet from a '85 Caprice that ran great when I pulled the engine about 2 yrs ago.
If you could find a Q-jet like that locally, you should get it. At least
you could drive your car until you found something better.

 

I know. I emailed a guy that had a couple spare bases laying around last I knew to see if I could get one cheap. Both bases had problems(one had stripped fuel filter threads, and the other was just worn too much) but I could use the throttle shaft out of either. If I cant get one from him I was planning on going junkyard hunting this weekend. I hope I can find something but we'll see.

Ben

 

Just to let you guys know. I got another base. I got a carb that was all gunked up and would have needed at least a major rebuild for 10 bucks. I soaked the base in carb cleaner over night and it looks nice now and there isnt play in the trottle shaft so hopefully this weekend the car will be running again.

Ben

 

let me guess here.....found it in a salvageyard......not off a thirdgen?

gary

 

Acutally, I am not sure. The junkyard that will let me go back and look for myself didnt have anything. This one made me bring mine in and they went to get something like it. They knew what kind of car mine was on and I could have told them anything that they wanted to know about it including any ports and even the numbers off of it but they made me bring it in anyway. I do believe it is off of an 83 something because where mine has 85 in the part number it has 83 and mine is off of my 85 Trans am and the other one I got from an 85 iroc has an 85 in that location also. Anyway like I said, I dont know what it was off of but it appears identical except it was all crusty and such.

Ben