Just installed new Quadrajet, secondaries not opening

[AirSpeed]

Got a summit Quadrajet installed on my 350, all went fine, engine started right up and runs smooth, revs fast and idles nicely but I can't get the secondaries to open. The valves open about 1/4 to 1/3rd and the upper butterflies only start to open. The spring tension seems stronger on the new carb than my old one. I bought this carb from a guy who bought it but never used it. The choke is wide open so it's not locking the secondaries out. Any ideas?
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[AirSpeed]

Originally Posted by AirSpeed

Got a summit Quadrajet installed on my 350, all went fine, engine started right up and runs smooth, revs fast and idles nicely but I can't get the secondaries to open. The valves open about 1/4 to 1/3rd and the upper butterflies only start to open. The spring tension seems stronger on the new carb than my old one. I bought this carb from a guy who bought it but never used it. The choke is wide open so it's not locking the secondaries out. Any ideas?
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[AirSpeed]

I just noticed the teams kickdown cable seems to be my problem, it won't allow the secondary linkage to travel far enough. The throttle cable and trans cable mounts although slightly different where the cables attach but they are in the same position as I set them side by side. My old linkage required a cotter pin to mount the trans cable, the new one required I slide the cable to the round hole in the end of the slot in the end of the cable, thanks for any suggestions!
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[Stocker]

My knowledge of carbs, including the Q-jet on my 350, is poor at best, so take this with a grain of salt. It's my understanding that the secondaries are vacuum operated and open on demand, so you're not likely to see them open in your driveway. Not much help, I know, but that's about all I have....

[AirSpeed]

Originally Posted by Stocker

My knowledge of carbs, including the Q-jet on my 350, is poor at best, so take this with a grain of salt. It's my understanding that the secondaries are vacuum operated and open on demand, so you're not likely to see them open in your driveway. Not much help, I know, but that's about all I have....

Thanks, the throttle plates open manually with the linkage, the air valves open with vacuum. It seems my TV cable is limiting the linkage from traveling far enough to open the fuel valves (the lower valves), the cable mounts on my old and new carb measure to be in the same position so I'm perplexed why I'm having this issue. Although my old carb is worn out I never had this issue before. I can open the secondaries by pushing on their linkage but not when I use the throttle, the TV cable seems short, just as the linkage starts to activate the secondaries the TV cable is fully extended and won't go any further. (Hope I'm not confusing anyone!)

[Boog]

So it has full movement with the trans cable disconnected?
Oh crap. You have overdrive don't you? As you well know that tv cable action has to be just right or trans damage is almost certain.

[AirSpeed]

Originally Posted by Boog

So it has full movement with the trans cable disconnected?

Yes, the secondaries operate with the cable disconnected, the cable seems too short. I held the carbs side by side and the mounts for throttle and the TV cable seemed to be in the same position. The linkage looks slightly different but I'm thinking there must be a difference in its throw. Is the TV cable adjustable?

[Bigdav160]

TV cables are adjustable BUT to control line pressure in your trans.

They used TH700 in carb applications so there should be enough travel.

Again proper adjustment and geometry are needed to have proper trans pressure

[Mr Handy]

If the trans cable is limiting the lower butterflies from opening then that is your problem. the other problem could be that the spring tension on the air valves/ upper butterflies is set to tight and not allowing the air valve to pop open at your engines full vacuum.
to set the spring tension there is a pair of screws on the choke side of the carb. on is a small flat head screw and the one underneath is an allen and locks the setting. a good starting setting is to loosen the tension until there is no tension on the air valve... or just enough to keep it closed. then tighten the tension one full turn and lock it down. drive the truck and punch the throttle at wide open and accelerate form say 30 mph if you get a bog when the secondaries open the spring is to loose. if you do not get a bog it could be to tight. loosen or tighten 1/4 turn of the tension spring. test drive again and adjust 1/8 turn to 1/16 turn past where the bog goes away and your secondary air valve should be set perfect.

[Boog]

Yes it is. There where it plugs into the bracket there should be a sort of round top. You press it down and cable housing should slide in or out of it. It's been a while since i messed with one of those. Anyway with the cable connected to the carb press in on that button and hold while you push the carb linkage to full open then release that button you were holding down. This will pull the housing out closer to where it needs to be. This should get the tv cable reasonably close.
This is assuming you have an OE type cable.

[AirSpeed]

Originally Posted by Boog

Yes it is. There where it plugs into the bracket there should be a sort of round top. You press it down and cable housing should slide in or out of it. It's been a while since i messed with one of those. Anyway with the cable connected to the carb press in on that button and hold while you push the carb linkage to full open then release that button you were holding down. This will pull the housing out closer to where it needs to be. This should get the tv cable reasonably close.
This is assuming you have an OE type cable.

That did it! Thank you! My button was on the bottom, cable must have been install 180 degrees in the bracket. Thanks again! Going for a test drive! Appreciate the help!
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[Boog]

You are very welcome. How did it shift?

[AirSpeed]

Originally Posted by Boog

You are very welcome. How did it shift?

Seems fine so far, I have a little hesitation from a standstill but it seems to cruise about five mph faster now, used to cruise about 60 now I find myself at 65. Sure starts a lot better and idles smoother. I'll mess around tuning it tomorrow, need to adjust the high and low idle.
Again thanks for the help!
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[Boog]

Originally Posted by AirSpeed

Yes, the secondaries operate with the cable disconnected, the cable seems too short. I held the carbs side by side and the mounts for throttle and the TV cable seemed to be in the same position. The linkage looks slightly different but I'm thinking there must be a difference in its throw. Is the TV cable adjustable?

You may want to have a tranny guy check the pressure. Some say the linkage geometry is critical to maintaining proper shift pressure. I'm sure you already know this but it's worth mentioning for others who may be new to 700R's.
The adjustment procedure I showed you above came straight from a service manual so it should be close. Happy motoring.

[AirSpeed]

Originally Posted by Boog

You may want to have a tranny guy check the pressure. Some say the linkage geometry is critical to maintaining proper shift pressure. I'm sure you already know this but it's worth mentioning for others who may be new to 700R's.
The adjustment procedure I showed you above came straight from a service manual so it should be close. Happy motoring.

I have a TH350, from what I've been able to find the TV cable adjustment isn't as critical as a 700R. I hope!
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[Boog]

Originally Posted by AirSpeed

I have a TH350, from what I've been able to find the TV cable adjustment isn't as critical as a 700R. I hope!
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Oh ok. My bad. I thought you had the od. Alls good then. 😉

[Bigdav160]

He did say "TV cable"

TH350 doesn't have a TV cable