How to understand automatic chokes part 4

[@piroguy14]

Great video!! i just bought a 79 caddy with a 425 and it has the same carb (obviously not original by the looks of it) with an electric choke. I wouldn't even have been able to distinguish between hot air or electric without your videos. I adjusted the choke and it started up on its own without any pedal for the first time since i bought it. Thanks so much

[@EnochianBorg]

I was watching this for reference on my classic VW carburetor and Choke settings. Thank you for posting these videos. I work on Chevy and VW and Buick.... So the Choke setting part was helpful. I have my choke a little too tight and its giving me problems setting anything else properly. I'm using a Solex 34 pict 4 was rebuilt by me so I know its all there and works but it's giving more smoke like you described and chug. Fixing that today!

[@TylersNeighborhoodGarage]

The heat stove in the intake has a long piece of steel tubing in there and sometimes that will rust out and disable the entire hot air choke. You can unbolt it and pull it out to check it. A good tip to keep the choke heated so that it does not close up so fast when you go in somewhere is to take the heater hose leading TO the heater core and loop it around so that it rests against the choke housing. Olds did this from the factory but lots of times the metal bracket disappears.

[@johnbeer5242]

Tyler's Neighborhood Garage 🏌🤔✌✌✌nice u are very helpful

[@WhiteLightning777]

What if you actually want to have a hot air choke and not an electric one, specifically for an Edelbrock carb? Is there a way to do that instead? My 1968 cougar currently has one with my Holley 4bbl. Problem is that the carb is HUGE and there's only a 302 V8 with GT40 heads. The engine builder used a Dyno and didn't actually set up the car for the real world, just wanted to chase 300 horsepower. It only had a mild Lupe but the power is either nothing with stalling or it spins the wheels and gets sideways, nothing in between. I'm downsizing to an Edelbrock 500cfm AVS2. It's either manual or electric, no way to work with original stuff. My hot air choke plugs it's metal tube into a small hole in the exhaust manifold and uses that temperature to work. My vehicle has no built in wiring for an electric choke whatever. That means that I have to get a relay and wire it up myself from scratch. I can do that but it's extra work and the hot air one is safer because heat tubes can't short out. I found that you can use the coil to signal a relay as long as it's not actually providing electrical power directly, just like wiring in a tachometer.

[@TylersNeighborhoodGarage]

@ralphie1320 I haven't had one of those for a long time, but if I remember correctly, the coil spring should have a small loop formed into it's "tail"...the end of the spring in other words. The choke rod should slide into that. BTW...your carb is a 4MV if it has divorced choke. 4MC has the integral carb-mounted choke. If I misspoke on the video I apologize. Thanks for watching.

[@JulienAbrahams]

I also look at the secondaries not opening up. It turned out that the connecting rod to the choke plate wasn't in the slot properly, keeping the tang on the air valves (air lock out tang?) so they couldn't open (which is correct for when the choke is on). As I set the rod properly, and the engine had warmed up and pulled the choke plate wide open, the tang was moved so the air valve could open, and it works well now.

[@TylersNeighborhoodGarage]

@kruss71 I would install a new fuel filter the very first thing. If that does not improve things then you will have to stress test it to see whether you have a fuel supply issue or not.

[@TylersNeighborhoodGarage]

You might have a broken spring or part of the linkage that came apart. I don't recall those having a lot of adjustment. Usually you have to bend the rod to the choke plate to effect an adjustment.

[@giovanniramirez5754]

Hello Tyler, I bought a reman carb for olds put it on and everything was fine except that it ides at 3000+rpms untill it is completly warmed up & another thing is if I go to a store and come back out 5 min later it starts the warm up process all over again. I was wondering what you would sugest that I do to solve this issue. Thank you So very much for these videos they are super helpful and now I have an idea of where to start.

[@TylersNeighborhoodGarage]

@JamesBerkey I would check the ignition timing first.

[@TylersNeighborhoodGarage]

@claude12343 The linkage is not precise, so a small amount of movement like you describe is negligible. I'm not sure what you mean by understanding cam follower, etc. The fast idle screw rests against the different steps, with fastest idle occurring when dead cold. Then, as the choke begins to heat and unwind, cracking the throttle a bit will allow the fast idle screw to move to the next lower step and so forth.

[@JulienAbrahams]

Hey Tyler, today I looked at it more closely and I think the problem is in the fast idle cam. I played around with it a bit, and then it worked. It pulled the choke plate close, and as the engine warmed up, the choke coil opened the plate as it should. When it is cold, it doesn't go into fast idle, so I think the fast idle cam needs adjustment. Before this I haven't worked on carbs, so I'm being careful, watching your videos (very helpfu!l) and using the shop manual as my guide.

[@TylersNeighborhoodGarage]

@MrTransAm1979 I know that particular carb well. You probably have a break in the hot air choke lines somewhere, or the paper gasket between the choke itself and the choke housing is missing. It HAS to draw in manifold heated air to unwrap and release the choke. Any kind of air leak and it won't do it.

[@TylersNeighborhoodGarage]

@chevysquarebody I don't think your truck has an actual "electronic" Qjet. It may have a connection on the right top front, but that's a dual-stage accelerator pump. If there are indeed two different connections then yes it is an "E4ME". They aren't necessarily that difficult to work with.

[@TylersNeighborhoodGarage]

I hope I understand what you are saying....the choke plate moves but it's not spring-loaded like it should be, right? If that's the case, then I'll describe how that connects together: There's a rod that leads straight down into the carb from the end of the choke plate as seen above. At the bottom end, there's a small metal piece that joins the rod to the choke shaft. It does not bolt or clip together, it's just a slip fit. You essentially have to look down in that hole from the top-con't

[@JulienAbrahams]

Hello Tyler, I got a '67 Cadi with a Q-jet carb, divorced choke. I have 2 questions. The first is about the choke. When the engine is cold, and I move the throttle lever so the primaries are openend, the choke valve doesn't close automatically (I can push it easily by hand though). When the engine has warmed up, the coil pulls the valve open. I suspect there is something the wrong way round as the Shop manual states that the coil should relax its tension when the engine warms up.

[@JulienAbrahams]

The second question is about the secondaries and the air vavle on top. How far should this air valve open up? Completely or just slightly. Because when I move the throttle lever past the primaries, the air valve is opened only by about 1/2 an inch (when the engine is running). Is this normal or should they open up completely (so that the air valve is vertical)? Thanks in advance. Julien Abrahams, The Netherlands.

[@giovanniramirez5754]

Awesome, Thank You so much for ur advice. Its much much appreciated. I will check this and see if I can handle it! Thanks again Tyler

[@tomsteffs6511]

Thanks for the info. My 85 Blazer was purchased brand new, never touched, it has original 90 thousand miles. I noticed that when I pump the gas pedal, the choke plate closes, once it starts the choke plate opens up upon warming up. But how much should it open? Straight up (90-degree) or less. The power is supplied to the electric thermostat thru the wire. I am besides myself with this one, I am getting hit in the pocket with the waste of gas too. LOL. Thank you again.

[@TylersNeighborhoodGarage]

Choke issue. The vacuum pull-off just cracks the choke plate slightly as soon as the engine begins to run. make sure you are getting a full 12v to the choke and that it stays powered up the entire time the ignition is on. Also, if it only has one wire connection it grounds through the choke housing so make sure no gasket between the choke and housing.

[@rexolive]

I sure could use your help. I have a 1983 Chevy C10. I have new plugs and wires and already checked the filter. I have been having problems off and on with my truck starting. I finally put a fuel pump in and it started right up and ran a day. The next day or day after it wouldn't start. It tries to turn over just don't know if it's getting gas. It looks like it's getting spark. Well that was in the morning. Later that day my wife was able to start it up with one try. It drove well the next day until this morning. Now it will not start at all. Hasn't started all day. I have cleaned the carburetor, rechecked the fuel pump install and still nothing. I'm at a loss and I can't afford to take it to a mechanic right now. It's my work truck and I really need to figure this out and get it going. Hope you can give me some advice. Thanks.

[@TylersNeighborhoodGarage]

Your problem is in the hot-air choke. There should a fitting on the intake manifold below the carb on the right side that has two metal tubes. The long one connects to a fitting at the top rear of the carb. The other connects to the choke housing. That has to be completely intact because the carb draws air through the long tube, through the heat stove in the intake and into the choke housing to warm up the choke spring and unwind it.

[@TylersNeighborhoodGarage]

No there's no set rule. They will open up only as far as needed and most stock engines won't move enough air to open them all the way even though a lot of people think they should. The main think is to have a smooth transition into the secondary side. You can play around with the secondary spring tension a bit until it works good but don't just loosen it until they flop open. It'll bog every time.

[@kruss71]

Hello Tyler, I recently bought a 81 Corvette about a year ago. Last weekend I decided to pull it out of the garage for a drive. I drove it the entire weekend but Sunday afternoon after driving it the entire day, I noticed some hesitation when got the speed up to 45 mph. After backing off the accelerator, the hesitation went away. When driving it again this weekend, it stalled...however it started right and drove about half a mile and stalled again. Do you have any ideas on what that could be

[@JulienAbrahams]

The funny thing is that I've owned the car for two years now, (my first American car) I just thought that it did not accelerate as fast. It is a pretty heavy car (about 5000 lbs) but still, it is a Cadillac with a 429 ci. Now I know that it was because the secondaries were just not opening. Now it really accelerates well when you put your foot down :).

[@Freizeitschranzer]

Thanks for your great videos! helped me a lot.. I just recognized today that my electric choke is not working and just not moving the primary to fully open. I adjusted it by just turning the box, after untightening the 3 screws. I noticed that the choke light stays on all time. Is this the same problem ? would be great if you have a hint for me (87´ Firebird L69 with E4ME Quadrajet) THANKS !!

[@TylersNeighborhoodGarage]

You'll need to check a few things: 1. That the choke is receiving 12v with the engine RUNNING, not just turned to ON 2. Whether the choke element is intact and passing the voltage it receives to ground. That is what heats it and causes it to open. 3. That the choke element does NOT have a gasket between it and the housing. I bet your issue relates to #1. Let me know.

[@JamesBerkey]

My car starts fine idles a bit high but when i am driven it seems like it has no power and feels like it has 100 mini backfires and once and a bit it gets a louder backfire. when the engine is good an warm you would pop off that air filter and notice the choke aint all the way open... but if i rev it up and keep the filter off it opens... i dont think i need a new filter. what are your thoughts.

[@TylersNeighborhoodGarage]

-look down in that hole from the top with the little metal piece hanging off the end of the rod, and start sliding the choke housing inward at the same time so that the metal piece engages the choke shaft. It's a real hassle. I suspect somebody pulled the choke off and then stuck it back together without doing that. An exploded diagram will help you a lot to understand this. Let me know if this didn't answer it.

[@TylersNeighborhoodGarage]

@piroguy14 Glad to help

[@bvnseven]

Rochester 2bbl 173 carb on a 2.8L S15. Last year the choke fast-idled but now it won't. A friend said to move the bakelite cuz it is probably too lean? I looked yesterday in 20° weather after it sat a while and the choke was still wide open. He told me go out and press the gas pedal and that is supposed to close the electric choke plate?? It did not close. Then he said check the one wire to the choke and make sure it's giving me 12v. I did and it is only giving 11.91v. He also said the choke plate seems loose and not attached. What is that previous video link you mentioned that will tell me all this stuff? I want to fix this myself.

[@zombieturd7]

i have a 84 olds with a 307 converted to electric choke. i am having issue with it not kicking off high idle some people say its a choke issue other people say choke pull off what you think it could be

[@Hacker2013able]

I understand way more about chokes. think back to all the engine problems that could have been fixed with a proper working choke. Thank You.

[@arthurgonzales8786]

on a 1978 Ford Van 351 eng. 2 barrel Carb.Elec. Choke. what is the voltage on it and where do you connect to? Thanks!

[@robberg9933]

Question for you. I have a carberated 4.3L in my boat. I'm new to this boat. When I start it it fires up right away and runs for a few seconds and stalls. After stalling I can turn it over continuously and it doesn't want to fire back up. I have killed my batteries on a couple occassions. At the end of last season I had my gf turn it over and I barely touched the choke flap and it fired right up. What is my issue here?

[@martinbeckmann9376]

Choke is too loose ( sloppy )

[@Few_politicians_run_your_life]

Hi Tyler's. My car is 1980 corvette with a brand new Rochester carburetor. My old Rochester ran very rough because it was dirty so, I replace with the new one. My problem is when the engine cold it start easy and smooth but the idle about 1400 rpm after 10 minutes the choke start to put the plate open all the way then the engine rpm drop very quickly and dies. Do you think I need to adjust something even it brand new carburetor or the vacuum line is the problem?

[@Crazyoffroadriders]

Hey can any one help me I just bought a El camino with that same carb on it but the choke is not connected because its not moving by hand when I took the the spring off or when I move the choke plate with my hand the place where the spring goes it doesn't move please help me because my car won't start un less I go and in gage the choke by hand

[@rprovasoli]

my choke/fast idle seem to be working correctly except for one thing. car gets up to operating temp, if i apply full throttle, running or not the fast idle cam takes over and it idles at 1500rpm. it will kick down and drive as it should until full throttle, any ideas?

[@zombieturd7]

thank you sir for the advice i will check it this weekend

[@bvnseven]

Part 2: It used to take 5 minutes for the engine to warm up w/fast idle working. Now it takes 10-15 minutes, fast idle doesn't work still. If I get froggy and want to leave early, the motor will jerk its head off. I can give it gas and the engine just seems dead until I let up on the gas and start over. This happens in all 3 gears and I never get to 4th gear. Then all of a sudden the carb starts to cooperate and it runs like it used to. I have had this thing rebuilt once, and he knows what he is doing. Air filter is clean also. Nothing else carb-wise has been changed other than the fast idle screw, but that doesn't matter when you are trying to warm the engine up, right?? There is one red wire connecting to the choke and somehow that plastic connector has a crack in it where I can see the prong leading to the choke. I had to wire tie it to keep it in place. I did listen to your other vids and I am going to go get another connector/cable for it. I am also going to wire brush the male and female ends on the current connectors to see if that makes a difference. The only other thing I didn't do is turn the key on to see if the choke plate closed. Is there a video that tells me the cables and linkages and how they are connected (Rochester 2.8L carb??) I can go get the number stamped on the carb if you need it. I remember a time when I started on this and I was told I needed that stamped carb number. Anything else I can do/ any other of your videos I can watch?? I have watched everything about carbs, parts 1 -4 already and am going to check the carb against them. Thank You Tyler.

[@im12runb4trouble]

secondary valves stay shut and wont start but if i hold tthem open starts and runs great. is this dangerous?...85 chevy 305,- 5L- 8 cyl

[@markmacewen6047]

Hi I'm putting a quad-jet with a electric choke on a older chev, someone said that I need a resistor on the power wire to the choke, is this the case if that is true how much of a resistor do I need ??

[@TylersNeighborhoodGarage]

You don't need a resistor. It uses a full 12 volts. Tell that person they don't know what they are talking about. Just make sure that the POWER SOURCE COMES ON AND OFF WITH THE KEY and has a fuse somewhere in it.

[@Crazyoffroadriders]

Thank you it was the plate at the end of the rod.

[@brenthenry1522]

Go my choke to working but now the four barrel wont kick in. When i take the vacum off of the choke tbey will kick in help

[@TylersNeighborhoodGarage]

Take a close look at the arrangement with the rod going from the choke pull-off up to the airdoor lever. The pull-off should be retracted and holding the airdoors closed at idle and low load situations. If you punch it, the vacuum signal drops to zero, the pulloff releases and the rod allows the airdoors to open. Try to visualize what is happening or not happening when you disable the choke pulloff. There's also a lockout lever on the choke linkage down low that locks out the secondary throttle blades until the choke is FULLY OPEN. You might have the choke adjusted a little too tight. You probably will find out what is going on pretty easily.

[@brenthenry1522]

Ok when the choke vacum is line is on the seconderies wont open the flaps on top barly move take tbe line off they open fine so do i need to ajust doors on top with the vacum conected

[@stevenolsen6360]

yes time 8.19 smokes stinks, that me after a mechanic, chasing another problem, never asked me how to start my engine, and helped himself to the setting, what price a damn phone call 2018.... did not these plate supposed to have a single breather hole, or a knob on the top edge to stop full closer?

[@tomsteffs6511]

My '85 Blazer k-5 has an electric quad-jet, and upon start up goes into high idle, but will never drop to low idle no matter if I drive it to the moon, the best is that when I try to shut down the truck it diesels so hard that the only way to avoid this issue is to shut it down in drive gear. Videos are informative, but man you have to be a scientist to figure out this primitive carburetor.

[@TylersNeighborhoodGarage]

Hah..even a caveman can do it :-) We can ignore the dieseling for now, that's a byproduct of the high idle. The very first thing to check whether the choke is functioning. With the engine at operating temperature, take a look at the carb and see whether the choke plate up top is open or mostly closed. If it's open, then you can assume the choke is working. What USUALLY happens is that the linkage on the passenger side of the carb adjacent to the choke housing gets gummy and won't release the choke high idle. Qjets are pretty sensitive to that. You can take carb or brake cleaner and spray it good, then use some PB Blaster and lube the linkage there. We are talking about behind the choke, next to the carb on the PASSENGER side. It wouldn't hurt to do the same on the driver side where the throttle cable hooks up. If the choke plate is closed, then you'll have to determine why the choke isn't operating. Those have an electric choke. First thing you do is start the engine, use a test lamp and see whether the choke is getting power. You can't do it without the engine running because the circuit goes through the oil pressure switch. If it is getting power but still not operating, then you'll need to investigate the choke unit itself. If it's been apart it will be held in by 3 screws. If it hasn't been, then there's 3 rivets. Check these things for now and let me know if you need to go further with the diagnosis.

[@toonse3683]

Shit u explain this so good tha I'm learning alot from it love this carburetor vids

[@sirlordwhitman]

12:25 'doo doo de doo.. gawdammit! piece o shit' yuk yuk yuk!

[@JeanPierre94061]

Here is a video of my 1989 Cadillac Brougham with an E4MC carb. This choke was set incorrectly, choke plate closed all the way and caused that blublublurgh idle. leaned it up and it solved my problem! kzbin.info/www/bejne/hmLChmCQh5mLrKs