Choke plate not closing.

[RustyPile]

Our trucks didn't come from the factory equipped with Holley carburetors.. The factory 4 barrel carburetors were QJets.. Although the adjustment procedures for both are very, very similar, the main difference is as I stated in an earlier post concerning voltage supply for the electric choke.. Check the factory service manual wiring diagrams and a normally open oil pressure switch will be found in series between the voltage source and the choke..

The wire has to be disconnected from the choke and the engine running in order to test for the presence of voltage.. With the choke wire connected and the engine running, the test light won't light up for the same reason the dash mounted "choke" light doesn't.. The heating element in the choke draws more current than that of the bulb..

Although it will probably work ok, I don't suggest eliminating the N.O. pressure switch and wiring an electric choke directly from the ignition voltage source.. If work is performed that requires the ignition switch to be turned on but engine not running, the choke will open during the process.. No "choke action" to aid in starting the engine will be available until the choke is allowed to cool..

 

[spanky55amg]

Make sure you have 12v at the carb though. Take a test light and make sure there’s 12v at the connector ...

Last time I checked, a test light cant measure voltage. *cough* But a DVOM could.

 

[spanky55amg]

The wire has to be disconnected from the choke and the engine running in order to test for the presence of voltage.. With the choke wire connected and the engine running, the test light won't light up for the same reason the dash mounted "choke" light doesn't..

I beg to differ. I can read 12+ volts at my choke with it plugged up and running with my DVOM.

 

[RustyPile]

Last time I checked, a test light cant measure voltage. *cough* But a DVOM could.

No need to choke on your words.. lol.. I didn't want to muddy the waters for the novice mechanic.. If the voltage needs to be measured, then yes by all means use a volt meter of some sort.. But as I stated, a test light works just fine when checking for the presence of voltage..

 

[RustyPile]

I beg to differ. I can read 12+ volts at my choke with it plugged up and running with my DVOM.

Me thinks you just want to argue with me, or you're trying to compare apples to oranges.. I never mentioned a DVM. Step away from your key board, and check the thing with a test light.. It will not light up.. A DVM of high impedance will indicate voltage because what little current is avaliable can be read by the meter, but not a test light.. You do know the difference between current and voltage???

 

[Frankenchevy]

 

[Dougnsalem]

Care if we join you?

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[spanky55amg]

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[Dougnsalem]

I may be weird or something, but I can tell the difference between 8 volts, and 12, using a test light. I can even tell 115 volts (that's the bright flash, followed by nothing....) I'm one of those older farts though, so I guess I could be doing something wrong all these years.

 

[Honky Kong jr]

I may be weird or something, but I can tell the difference between 8 volts, and 12, using a test light. I can even tell 115 volts (that's the bright flash, followed by nothing....) I'm one of those older farts though, so I guess I could be doing something wrong all these years.

No not at all. Your just like the rest of us that don’t need to be spoon fed information on a screen.

 

[Honky Kong jr]

I may be weird or something, but I can tell the difference between 8 volts, and 12, using a test light. I can even tell 115 volts (that's the bright flash, followed by nothing....) I'm one of those older farts though, so I guess I could be doing something wrong all these years.

Although a lot of the stuff I work on is 5v and down so a meter helps as does an oscilloscope.

 

[Dougnsalem]

Although a lot of the stuff I work on is 5v and down so a meter helps as does an oscilloscope.

Yeah, that's understandable for stuff like that. Sensors too....

 

[84 Shorty]

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Thanks Dr House

 

[Dougnsalem]

Thanks Dr House

You bet. That was my honest attempt to help. Not a bad video....

 

[QBuff02]

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.