Manual choke won't work right on 79 Rochester 3GC carb

[boltbrain]

My 79 with a 350 had a automatic choke that had been butchered up so bad I put a manual choke on it. But it's not working too good and was hoping somebody could give me a tip or two on how to get it set up right. The main problem is the outer shield on the cable doesn't have anything to mount to thats closer than about 5" from the butterfly valve, so there's some flex in it. It works but its kind of mushy. Maybe just a thicker cable would work but the other problem is with the idle speed cam. It won't allow the choke cable to move without flooring the throttle pedal. And thats not always easy to do when the weather is cold. I'm tempted to just grind some of the metal off the cam so it still idles up a little when it's choked.
I looked for a choke kit thats just for this truck but it all I've found is universal kits
Thanks

 

[Terlingueno]

Fabricate a mount that fits under the rear passenger side carb to manifold bolt

 

[goldpack]

is this the one you bought ?

https://www.lmctruck.com/fuel-system/carburetor-parts/manual-choke-conversion-kit-gm-dodge-4

just making a quick look at classic industries website, they have a selection of cables and linkage for carbs,

https://www.classicindustries.com/shop/1979/chevrolet/c20/parts/fuel-system/carburetor-components/cable-linkage/

 

[boltbrain]

Fabricate a mount that fits under the rear passenger side carb to manifold bolt

I'll look at it and probably do that. I'll post a picture of it. Thanks

 

[boltbrain]

is this the one you bought ?

https://www.lmctruck.com/fuel-system/carburetor-parts/manual-choke-conversion-kit-gm-dodge-4

just making a quick look at classic industries website, they have a selection of cables and linkage for carbs,

https://www.classicindustries.com/shop/1979/chevrolet/c20/parts/fuel-system/carburetor-components/cable-linkage/

Not the one I bought but I might get that LMC one, I don't have the truck here but it looks good.
Didn't know about Classic industries, I'll write that one down, looks amazing

 

[Ricko1966]

You are supposed to floor the truck to set the choke and the fast idle cam,that's the way it was designed.

 

[fast 99]

those universal choke conversion kits were at best horrible. Engine will be much happier if the preheat system can be restored, intake crossover passage open and working heat riser, ect.

 

[xm20k]

Due to the conversion of an automatic choke with high idle on a factory carb you have four options.

Source the original parts and put it back to stock. Some of these parts may be hard to find or of questionable quality. Here and/or ebay may help.

Replace the entire carb with an electric choke version. Save your pennies as a good quality reman/rebuilt stock Q jet can cost as much or more than an aftermarket carb if you don't have a builder nearby.

Disable the high idle mechanism so the choke operates only with the cable. I've seen a ton of Q jets with issues due to people going this route and messing up stuff that isn't even part of the high idle mechanism.

Step on the pedal pull cable let warm then tap the pedal as you push the cable back in, so the high idle side doesn't interfere.

There is a fifth, but I won't go there as that involves a bunch of aftermarket parts and/or an adaptor.

 

[Ricko1966]

I am going to assume you have a 2gc, I've never heard of a3gc,,,,, all I know is 2gc or 4gc here is an electric choke kit for a 2gc

 

[boltbrain]

Sorry for the late response, been busy. Thanks for all the great information, it’s this kind of help that keeps me interested in this truck. I haven’t been able to drive it enuf to know if it uses oil (3rd gear is out) or even do a leak down test but I think I’ll go ahead and get a good 2GC for it, as it’s backfiring and flooding at times and I’d like to have all those features like electric choke, pre heat, etc. Where’s a good place to find one? I saw one used one on eBay for $200. Was thinking if the engine needed rebuilding I could put my 292 in it but it is a 3/4 ton 4x4.
I know it’s normal for the fast idle to kick in or out with throttle pedal down with manual choke but on this it was not working right, with the accelerator pump on the carb worn out. At least that’s what it acted like.
The engine is all original except for the manual choke so maybe I can get it all back to normal. Many thanks

 

[DoubleDingo]

Do you have the 292 passenger side frame mount? You'll need that if you swap the 292 in, as the passenger side mount sits further forward and has a specific frame mount. If you don't have one you can order one from 12bolt.com

 

[boltbrain]

Do you have the 292 passenger side frame mount? You'll need that if you swap the 292 in, as the passenger side mount sits further forward and has a specific frame mount. If you don't have one you can order one from 12bolt.com

Thanks, I don’t have one but I’ll order from them if I order.

I was looking at the 2GC pics on EBay and see they are 2 barrel, well I have a 4 barrel, but the two probly gets better mileage? Guess I need an intake too now. Did they put 4 barrels on stock?

 

[DoubleDingo]

Before we go any further, take some photos of your carb and post them up so we can see what you have.

 

[Ricko1966]

Why don't you show us a pic of this 3gc carburetor you were asking questions about.

 

[boltbrain]

Here it is