Choke plate not closing.

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Honky Kong jr

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https://www.hemmings.com/magazine/mus/2009/10/The-Lost-Art-of-Choke-Adjustment/2144991.html

http://www.chevelles.com/techref/Adjusting_Automatic_Chokes.htm

A few articles for reading fodder..

Now, I'm really non-partisan to the argument, er-discussion because to tell that family secret again.. I run Demon Carbs on my stuff, and when they work they are sickeningly awesome! And when they don't, well, they're Holley's red headed step child! Lol! When I bought my truck I had all kinds of problems with getting it to run, from a totally misadjusted carb, to a choke that was mediocre at best and to top it off was fed power via scotch lock to the 12 volt+ on the distributor connector by the previous owner! There are a couple of different choke styles throughout the years, but the most common one that we all generally have uses the little bi-metallic spring that heats up when it is fed power (like in the original posts picture) but that's also assuming that the choke is adjusted right, the fast idle is adjusted right, and the adjustment rods are in the right places.. I'd start by checking to make sure that the fast idle cam (if that's the carb in question in the picture, it's the little red lever behind the choke element) moves free with the throttle depressed. I've seen the little teenie tiny clip that holds the arm in place behind that assembly fall out or rot/fall off and the linkage binds not allowing the fast idle to work properly. Also, verify that it HAS 12 volts at the choke, and make sure positive is on positive and negative is on negative. Yes, i've seen them hooked up backwards. Also, look where the linkage rod goes up through the air cleaner flange to the butterfly on the choke, there's a small plastic guide (if it still has it) that if/when it gets worn will shift from proper position and not allow the linkage to move freely through the slot and bind up thus not allowing the butterfly to operate accordingly and I've seen them get stuck shut AND open! If, and only if at that point if everything appears to be correct, would I move forward with trying to adjust the choke and carb. So starting off cold, I'd turn the key on and stab the throttle one time. And verify the position of everything. Even with the engine off (assuming you still have 12 volts because we don't know where it's getting power from) and the bi-metallic spring working correctly you should be able to watch the choke "pull off" on it's own as the element heats up. There again, all the linkages and assembly should be free. From there, I'd work on adjusting the carb itself. Start with the basics and go from there. And verify idle speed with it warm, that could cause cold start issues as well. Hate to cut it short but it's Valentine's day and I want to get home from work to homemade tacos for dinner! Hope some of this helps. :handshake:
I like tacos
 

84 Shorty

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So I pulled my electric choke off and compared it to a brand new choke at the auto parts store. The coil inside my choke seemed like it wasn’t as wound up tight and felt weaker...if that makes any sense. This could have been from me twisting on it a little too much. But I’m just going to blame it on the PO, like I do everything else.
 

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So I pulled my electric choke off and compared it to a brand new choke at the auto parts store. The coil inside my choke seemed like it wasn’t as wound up tight and felt weaker...if that makes any sense. This could have been from me twisting on it a little too much. But I’m just going to blame it on the PO, like I do everything else.

The spring can be damaged from excessive twisting of the cover.. Reinstall it and go through the adjustment procedure in the video @Dougnsalem posted for you.. Pay particular attention to the part about indexing the choke housing and the cover.. When the choke is fully closed, if the index markings are within the prescribed range, the spring might be ok..
 
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Dougnsalem

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Choke issue fixed. Electric choke was way out of adjustment. Also, high idle set screw wasn’t even doing anything.
Good deal. Simple fix....
 

Honky Kong jr

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No, I haven't learned. Yeah, I watched it. I don't know wtf it was, but I watched it.... Lol
I’m not a fan of that genre of music , but that song speaks to me. The footage from a movie. The real video has a gold toothed hood rat in it, well a bunch of them. Plus it’s funny when the guys leg flops like silly putty at the end.
 

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Great news... And kudos for coming back and giving the update..
 

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Rusty, way back you mentioned the choke break, aka choke pull off. This Holley doesn't have such a device. It just hopes the engine vacuum can pull the choke plate open, thus ending the major rich condition a closed choke plate causes.
One thing I noticed is that few posters know how a choke system works.
If one pulls the air cleaner, you can watch the choke going thru its motions. If you crack the throttle r e a l l y gently, you can see and feel the choke plate incrementally move closed, and feel the fast idle cam acting on the fast idle screw, which usually has 2 or 3 steps.
When I ran a gas Suburban (all diesels now) I could set the choke half closed and a slower fast idle by pressing the gas pedal real easy, thus only allowing half the choke-fast idle step up. If you've got a sensitive toe, you can feel the light clicking at the gas pedal.

Getting back to the electric choke, loosen the 3 screws, and with cold engine, throttle held open (more than 1/4 travel) the choke plate should lightly close. If it gets colder outside, the bi-metallic spring will close it tighter etc. I'd rather have it closing "lighter" as closing too tight will cause a rich condition ie-dumping raw fuel into your cylinders, washing off the oil and fouling your plugs and catalityc converter. GM went from intake-exhaust crossover chokes to electric in the mid 70's, in combination with a vacuum pull off. In fact they used 2 pull offs. A quick acting pot in the front of the carb, and a metered pull off in the back. The rear pull off also serves to hold the 4bbl secondarys closed for a few seconds when your into them, thus saving you from wasting fuel and getting the large secondary plates to flop open. Remember, the metered 2ndary pull off? Yup, it holds the secondary top plate closed. One of my tricks way back was to remove this rod and drop it into the air cleaner pot for "safekeeping". Leave the 2nd pull off rod in place and you still get the backup choke pull off action.
Have you had enuff??? There's also a pre-load secondary spring adjustment, hidden, to hold back your lead foot. All the above applys to the spread-bore Q-Jet.
 

CORVAIRWILD

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Oh, and if I knew how to use a meter as well as I can adjust a Q-jet...

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RustyPile

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Rusty, way back you mentioned the choke break, aka choke pull off. This Holley doesn't have such a device. It just hopes the engine vacuum can pull the choke plate open, thus ending the major rich condition a closed choke plate causes.
One thing I noticed is that few posters know how a choke system works.
If one pulls the air cleaner, you can watch the choke going thru its motions. If you crack the throttle r e a l l y gently, you can see and feel the choke plate incrementally move closed, and feel the fast idle cam acting on the fast idle screw, which usually has 2 or 3 steps.
When I ran a gas Suburban (all diesels now) I could set the choke half closed and a slower fast idle by pressing the gas pedal real easy, thus only allowing half the choke-fast idle step up. If you've got a sensitive toe, you can feel the light clicking at the gas pedal.

Getting back to the electric choke, loosen the 3 screws, and with cold engine, throttle held open (more than 1/4 travel) the choke plate should lightly close. If it gets colder outside, the bi-metallic spring will close it tighter etc. I'd rather have it closing "lighter" as closing too tight will cause a rich condition ie-dumping raw fuel into your cylinders, washing off the oil and fouling your plugs and catalityc converter. GM went from intake-exhaust crossover chokes to electric in the mid 70's, in combination with a vacuum pull off. In fact they used 2 pull offs. A quick acting pot in the front of the carb, and a metered pull off in the back. The rear pull off also serves to hold the 4bbl secondarys closed for a few seconds when your into them, thus saving you from wasting fuel and getting the large secondary plates to flop open. Remember, the metered 2ndary pull off? Yup, it holds the secondary top plate closed. One of my tricks way back was to remove this rod and drop it into the air cleaner pot for "safekeeping". Leave the 2nd pull off rod in place and you still get the backup choke pull off action.
Have you had enuff??? There's also a pre-load secondary spring adjustment, hidden, to hold back your lead foot. All the above applys to the spread-bore Q-Jet.

Yep.... Over the years, the venerable ol' Q-jet went through (endured??) numerous changes.. "Heated by exhaust gases" hot air choke - a sort of controlled vacuum leak.. A divorced choke, electric choke, and probably some I've left out.. On the big trucks, even a manual "pull the knob" choke.. Front mounted choke break, rear mounted "combination" break, and even a break mounted at both ends.. Us old guys used to joke about GM making sure if one break didn't get it coming, the other one would get it going.. It all culminated with the CCC version with the metering rods that "jacked off" in order to deliver fuel...

Yes indeed, those were the good old days.. Thanks for walking with me down memory lane..

Oh, BTW, I'm sure there's a meter for checking those rusty fenders.. lol...
 

bucket

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Oh, BTW, I'm sure there's a meter for checking those rusty fenders.. lol...

That would be a body pick hammer. AKA, the rusted metal integrity tester.
 

Joshua Keith

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Choke issue fixed. Electric choke was way out of adjustment. Also, high idle set screw wasn’t even doing anything.

So your choke closes on its own now overnight now? Mine has never closed back on it’s own, wondering if mine is broke too. Lol Before I attempt to start my K10 I have to pump the throttle once then the primary blades close. Cranks first try.
 

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