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Old 07-12-2012, 03:20 PM   #1 (permalink)
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Toyota 22r Carburetor - lots of pictures

Alright, I have a bunch of pictures here of my toyota 22r carb, hopefully they will help out sombody in the future. I currently have it in pieces still, so let me know if you want to see any other photos, but give me a minute, as this will take me a while to post. Also, I am by no means an expert so please add/correct me wherever you see fit. Edit: it is now back together, so I am just going to whore out the pictures in this thread whenever somebody has a question about these. Tough nuts if you want a special picture

Edit to add links with more info: http://www.bluebassdesign.com/boonin/carb_faq/ How to get it with a toyota carb Stock carb pics

Application is 1987 22r California 4wd. Buy a haynes/chilton for your specific layout



Here is how it looks under the hood. You may notice that I am not running the intake hose beyond the hot air intake. I did fail Ca smog visual because of this, so for inspection purposes, run all the way out to behind the head light, then remove unless you like water when it rains.



Remove top of the air filter housing and you can see the top of the carb, along with some vacuum doodads that work with the hot air flap in the intake tube.

My choke/high idle cam don't work properly, so in the event of a hard start; manually close the passanger side butterfly valve and it will fire right up.



Remove: 2-12mm nuts, one at the front of valve cover, one at rear near throttle cable, crankcase vent tube, vacuum lines and the air filter housing comes off. Here is a bottom side view.



Here is a view of the top of the carb, I circled in green the lines that will need to be removed for on vehicle adjustments.



Here are other pictures of the various sides, let me know if labels would help.

Passanger Side



Drivers side



Drivers side, again



More to come...
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Last edited by Provience; 07-14-2012 at 02:27 PM.
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Old 07-12-2012, 03:31 PM   #2 (permalink)
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To remove the top 1/3 of the carb, remove but DO NOT LOSE the tiny hair clips holding these arms on.



Then remove the 4 philips head screws and lines.



Here is the piece you have just liberated, next to the main bowl.



Float, needle and seat.



Open



Closed. That is the little tab that you bend so that you can adjust the level of fuel before the float closes the valve. Trial and error has always worked for me, I run the bowl somewhere in the bottom half of the glass window.




Be mindful that this tab on the backside can also influence the float if you are not aware of it. It can contact the float bowl and prevent the float from fully closing the valve, resulting in flooding. This view is with the valve closed.



open



More to come....
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Last edited by Provience; 02-25-2013 at 06:07 PM.
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Old 07-12-2012, 03:36 PM   #3 (permalink)
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Top down view of the throttle plates.

Note both plates closed



For some reason I flipped over my camera, so the passanger side is on top. Note the passanger plate is partially open at roughly half throttle, driver side plate closed



Throttle fully open, both plates fully open, maximum airflow.





Pictures of vacuum lines, just because.











More to come....
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Old 07-12-2012, 03:41 PM   #4 (permalink)
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To remove the whole thing from the truck, First remove the two 12mm bolts that hold down the throttle cable cam, and remove said part.



Unbolt the 4 12mm nuts that hold the carb to the manifold. They are visible in the above photos of vac lines. The rear passanger one happens to be a bolt, be aware. Use an extension to get to the two drivers side, and a combo wrench for the passanger side.

here is what remains, notice that many of the vacuum lines do not need to be removed.




Eating dinner right quick, less than 20 more pictures to go...
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Old 07-12-2012, 04:03 PM   #5 (permalink)
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Convince the wife that her kitchen should smell like gasoline and the table could use a couple scratches, time to move out from the heat

Drivers side



Front view



Passanger side



Rear view




If you are not getting the "spit" of fuel when you apply the throttle, check into this valve, if torn it will result in performance issues due to not getting the extra fuel for acceleration it provides.



Here is a shot of the actuator arm. Remove the 4 philips head screws.



Here it is open, spring/valve need to both be in good condition. Mine has some shit that has collected in there, good time to clean it out.

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Old 07-12-2012, 04:20 PM   #6 (permalink)
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Here is a shot of the linkage clusterfuck. The stepped fast idle cam is in the center of the picture.



Here is a view of the plates open from the bottom.



Here is a close up of the little arm/spring combo that opens the driver side plate. If you have issues with the secondary not opening, check here to verify correct assembly.



Begin by removing this throttle return spring.



Here is another lovely little hair pin to remove. There are many, check every arm for one.



Remove this 10mm nut.



Another clip to remove this vacuum modulator.



And the 2 screws that hold the assembly on.



This landing pad for the high idle screw then slides off.



More to come...
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Last edited by Provience; 02-25-2013 at 09:17 AM.
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Old 07-12-2012, 04:20 PM   #7 (permalink)
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Clip and 2 screws to remove this vacuum modulator on the rear/driver side.



Remove this bolt to pull off the fast idle cam glob.



Now you can easily see your idle screw and its landing pad on the main linkage, let's call it body.



Now to seperate the remaining 2/3. Remove the 3 flat head screws.



The two sections next to each other.



And there you have it.

If anybody would like to add anything, please do. I know that there isn't any tuning info or anything in here, feel free to add if you like.
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Old 07-12-2012, 04:48 PM   #8 (permalink)
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Which port goes to the vacuum advance

a,b, or c?
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Old 07-12-2012, 05:02 PM   #9 (permalink)
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Quote:
Originally Posted by rockyota83 View Post
Which port goes to the vacuum advance

a,b, or c?
Port A goes to the front port on the distributor (closest to radiator)port on the distributor vacuum modulator.

The rear (closest to firewall) goes to the bottom switch in this picture


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Old 07-12-2012, 05:14 PM   #10 (permalink)
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Awesome. Wish this was posted 4 years ago.
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Old 07-12-2012, 05:17 PM   #11 (permalink)
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Originally Posted by realmencutfenders View Post
Awesome. Wish this was posted 4 years ago.
Hopefully it helps some people out. Ideally, others will be able to add with more questions and answers and shit.

Tomorrow or saturday I will probably put it back together, if I take my time and get the choke and fast idle cam setup properly then I will add those pictures in as well; of them correct
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Old 07-14-2012, 01:58 PM   #12 (permalink)
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Here are a couple more shots of the inside.

I am going to find the quote from another thread regarding this fuel rail for the secondary and insert it here.

Quote from Ryanonthevedder:

Quote:
The primary venturi is the one with the choke flap on it. It should open up and stay open after a few minutes. The other side is the secondary venturi. The flap on that side is there to help draw fuel in through the main jet. The fact that you were able to get it to work by closing either the choke or that other plate means that.... wait for it... the secondary fuel metering system is plugged. Yay!

I was hoping you might figure it out on your own, but I ve worked under the hot sun so I'll throw you a bone.

Pop the top off of the carb, and remove the secondary jet. Make sure it is perfectly clean. Next pull the fuel rail out of the secondary venturi. Its the square looking aluminum thing that runs across the bore. It is held in by a steel wedge on the far side. It needs to come out before.

Dont drop it into the carb !!!

Make sure it is very clean. Spray carb cleaner through the hole where the jet was and make sure it comes right through to where you removed the rail.

Put it back together and go ask that mechanic why he did such a shitty job.
22r oh god help me


Pictures of how to remove, pull upward evenly. Don't loose the spring.



Here it is next to the "spring" that helps hold it in place. Notice the cutout on the rail, keeps you from puting it in backwards



Here is just another reference shot. Inside of the bowl, valves, jets, etc. the black tube just pulls up, here it is partway out.



I did a good of messing around with the choke linkage, this works on paper, should also work well on the truck Here it is in the "open" position.



Here is is closed, notice how the stepped cam is now in position to keep the throttle blade open for high idle.



Here it is again, this time with the choke control vacuum regulator attached.



Here is a picture of what I was eluding to with xtoyota and his potential linkage issue. This is an upskirt view of what happens when the choke is applied, this lever keeps the secondary plate from opening, even with full throttle applied, as in this picture. Helps prevent over-revving a cold engine, and why performance suffers so dearly while the choke is set.



Let me know if you can tell in this picture, if not then I will highlight what I am talking about.

And fully assembled again.

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Last edited by Provience; 07-14-2012 at 02:05 PM.
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Old 07-14-2012, 10:29 PM   #13 (permalink)
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Nice job- just added it to the FAQ
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Old 07-15-2012, 05:09 AM   #14 (permalink)
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Nice write up.
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Old 07-15-2012, 08:53 AM   #15 (permalink)
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Thanks guys. Iffn anybody comes across some more good info or tuning stuff, feel free to add to it.
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Old 07-15-2012, 11:31 AM   #16 (permalink)
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I have prob over 100 used carbs of all years. We should get together and YOU should rebuild them for me.
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Old 12-25-2012, 04:19 PM   #17 (permalink)
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First let me say I appreciate the photos. I am having cold start issues. I might be wrong, but it looks like you have the choke breaker and choke opener vacuum lines reversed. The breaker is on top and is running to vacuum. The opener runs thru the bvsv so once the engine warms up the choke is forced open (bvsv opens and lets vacuum thru)


Quote:
Originally Posted by Provience View Post
Alright, I have a bunch of pictures here of my toyota 22r carb, hopefully they will help out sombody in the future. I currently have it in pieces still, so let me know if you want to see any other photos, but give me a minute, as this will take me a while to post. Also, I am by no means an expert so please add/correct me wherever you see fit. Edit: it is now back together, so I am just going to whore out the pictures in this thread whenever somebody has a question about these. Tough nuts if you want a special picture

Edit to add links with more info: 22R Carburetor FAQ How to get it with a toyota carb Stock carb pics

Application is 1987 22r California 4wd. Buy a haynes/chilton for your specific layout



Here is how it looks under the hood. You may notice that I am not running the intake hose beyond the hot air intake. I did fail Ca smog visual because of this, so for inspection purposes, run all the way out to behind the head light, then remove unless you like water when it rains.



Remove top of the air filter housing and you can see the top of the carb, along with some vacuum doodads that work with the hot air flap in the intake tube.

My choke/high idle cam don't work properly, so in the event of a hard start; manually close the passanger side butterfly valve and it will fire right up.



Remove: 2-12mm nuts, one at the front of valve cover, one at rear near throttle cable, crankcase vent tube, vacuum lines and the air filter housing comes off. Here is a bottom side view.



Here is a view of the top of the carb, I circled in green the lines that will need to be removed for on vehicle adjustments.



Here are other pictures of the various sides, let me know if labels would help.

Passanger Side



Drivers side



Drivers side, again



More to come...

Last edited by rlwoodjr; 12-25-2012 at 04:26 PM.
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Old 12-25-2012, 04:37 PM   #18 (permalink)
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Wouldn't surprise me, hence sentence 3 in post 1


As i mentioned, i was also having a cold start issue directly related to choke issues. I just assumed it was linkage related. The choke plate would not close on its own and it felt like a slight bind, pop the air cleaner cover off and gentle press it and it would hold closed and fire right up. Never a issue warming or warmed or running there after, just wouldn't set itself off the bat.
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Last edited by Provience; 12-26-2012 at 01:02 PM. Reason: info added in post below
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Old 12-26-2012, 12:59 PM   #19 (permalink)
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Quote:
Originally Posted by rlwoodjr View Post
it looks like you have the choke breaker and choke opener vacuum lines reversed. The breaker is on top and is running to vacuum. The opener runs thru the bvsv so once the engine warms up the choke is forced open (bvsv opens and lets vacuum thru)
Alright, I definitely did have the Choke Breaker (cb on haynes diagram) running to the vsv and the Choke Opener running to vacuum.

After looking with scrunchy eyes at the diagram, it does appear that you are correct and the Choke Breaker (located on top of carb and inboard side of the electric choke) should be running to the Jet and Vacuum and the Choke Opener (located immediately below Choke Breaker) should be running to the BVSV.



Thanks for the heads up
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Old 12-26-2012, 04:56 PM   #20 (permalink)
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Useful info for those who still work on those things. I'm about to remove the carb from my 85 and sell it on Ebay.

I like the simplisity and performance of a good 'ol Weber 32/36DGEV.
Now days you can find the whole swap kit for right at $300.
I guess some people who still have to have the older trucks inspected then I can understand.

Still good info for those who need to work on them.
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Old 01-02-2013, 04:49 AM   #21 (permalink)
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22r stumble

Lovely! My '86 22r has treated me well for 15 years or so, it's stock, but now has the 'dyslexic stumble' in it's favorite RPM range (low). It starts fine (well, the float bowl drains overnight now, what's that about?) and doesn't start acting up until it's half warm. Disarming EGR has no effect.
How does the power valve thingy work? I took off the lid and sprayed cleaner and blew all the passages I could find out. The 'metering rod' is for the secondary, correct?
I saw all 'pinhead's videos, but I'm not quite ready to rip it apart...there wasn't any crud in the bowl, and I can't even buy a kit anymore up here in Vancouver. BC.
What's pinheads's 'native' forum anyway, or is he just one of those selfless cats that's everywhere?
For that matter, it could be just feeble ignition. Usually you have an idea if it's a fuel or ign prob, but the temperature & intermittent-ness has me stumped.
I even gave her the old HEI transplant...she could throw a 1/2" arc triggering the module with a flashlight battery, but with the original pickup coil, nothing. I thought it might relate to a higher voltage to fire a leaner mix or suchforth.
But now I'm probably 'cross-posting '!
Any thoughts are much appreciated
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Old 01-02-2013, 09:33 AM   #22 (permalink)
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Quote:
Originally Posted by hashwin View Post
Lovely! My '86 22r has treated me well for 15 years or so, it's stock, but now has the 'dyslexic stumble' in it's favorite RPM range (low). It starts fine (well, the float bowl drains overnight now, what's that about?) and doesn't start acting up until it's half warm. Disarming EGR has no effect.
How does the power valve thingy work? I took off the lid and sprayed cleaner and blew all the passages I could find out. The 'metering rod' is for the secondary, correct?
I saw all 'pinhead's videos, but I'm not quite ready to rip it apart...there wasn't any crud in the bowl, and I can't even buy a kit anymore up here in Vancouver. BC.
What's pinheads's 'native' forum anyway, or is he just one of those selfless cats that's everywhere?
For that matter, it could be just feeble ignition. Usually you have an idea if it's a fuel or ign prob, but the temperature & intermittent-ness has me stumped.
I even gave her the old HEI transplant...she could throw a 1/2" arc triggering the module with a flashlight battery, but with the original pickup coil, nothing. I thought it might relate to a higher voltage to fire a leaner mix or suchforth.
But now I'm probably 'cross-posting '!
Any thoughts are much appreciated
On lunch, so this is quick, let me know if it helps you at all...

I have no idea what/who pinheads is a reference to....so... on whatever that means.

Where is the fuel going? Overnight is way to quick for that thing to be draining out, sounds like you have a jacked seal somewhere. If you cannot get a rebuild kit in BC, there are tons of them here in the states, can't imagine it would be that fucked to ship one up there.

Personally I have always had the best ignition luck with factory coils/ignitors on stock or mild engines.

I pretty well suck with terms, so I am going to copy and past these from MuscleCarClub.com, some generic but good definitions.

I would only like to add Power Valve, as it is not listed and that is what I have always known it as. The PV is the valve that is sends in a large shot of fuel into the venturi with the application of the throttle independent of engine vacuum. On the toyota carb it is the square valve on the pass. side, on some other brands like Holley, they use a round rubber plunger style. This helps quickly provide the fuel that the carb needs to accelerate quickly.

Musclecarclub.com - Library - Tech - Carburetor

Quote:
Carburetor



The purpose of the carburetor is to supply and meter the mixture of fuel vapor and air in relation to the load and speed of the engine. Because of engine temperature, speed, and load, perfect carburetion is very hard to obtain.

The carburetor supplies a small amount of a very rich fuel mixture when the engine is cold and running at idle. With the throttle plate closed and air from the air cleaner limited by the closed choke plate, engine suction is amplified at the idle-circuit nozzle. This vacuum draws a thick spray of gasoline through the nozzle from the full float bowl, whose fuel line is closed by the float-supported needle valve. More fuel is provided when the gas pedal is depressed for acceleration. The pedal linkage opens the throttle plate and the choke plate to send air rushing through the barrel. The linkage also depresses the accelerator pump, providing added gasoline through the accelerator-circuit nozzle. As air passes through the narrow center of the barrel, called the "venturi", it produces suction that draws spray from the cruising-circuit nozzle. The float-bowl level drops and causes the float to tip and the needle valve to open the fuel line.

To cause a liquid to flow, there must be a high pressure area (which in this case is atmospheric pressure) and a low pressure area. Low pressure is less than atmospheric pressure. The average person refers to a low pressure area as a vacuum. Since the atmospheric pressure is already present, a low pressure area can be created by air or liquid flowing through a venturi. The downward motion of the piston also creates a low pressure area, so air and gasoline are drawn through the carburetor and into the engine by suction created as the piston moves down, creating a partial vacuum in the cylinder. Differences between low pressure within the cylinder and atmospheric pressure outside of the carburetor causes air and fuel to flow into the cylinder from the carburetor.

A larger carburetor or throttle body will enable the engine to draw in more air, but one that is too big is almost as bad as one that is too small. On a fuel-injected car, a throttle body that is too big will put too much gas in the combustion chamber that just flows the exhaust unburnt. It is much more of a problem on a carbureted car. There, an oversized carb will make the engine actually perform worst at part throttle. A simple formula for calculating the correct carburetor setup is:

CFM (amount of air the engine needs) = Displacement (in cubic inches) X Maximum RPM / 3,456


The result is usually rounded up to the next largest off the shelf carburetor sized. Therefore, a Chevy 350 built to redline at 6,000 rpm would need 608 cfm of air flow (350x6000/3456). A Holley 4150 carb rated at 650 cfm would be a good choice. For multi-carb setups, don't forget to add up the CFMs for each carb!

Once you find the right carburetor, keeping it tuned correctly is key. Also, carb spacers and carb re-jetting usually help, but it requires trial and error to find the best combination.


Venturi



"Barrel" is a popular term for the carburetor throat. There is one venturi in each throat. A two-barrel carburetor has a primary venturi for part-load running and a secondary venturi for full-throttle; a four-barrel carburetor has two primary and two secondary venturis. The venturi tube is important in carburetion. A "venturi" is a tube with a restricted section. When liquid or air passes through the venturi tube, the speed of flow is increased at the restriction, and air pressure is decreased, creating an "increase in vacuum" (a reduction in ambient pressure). This causes fuel to be drawn into the barrel. The venturi action is used to keep the correct air-fuel ratio throughout the range of speeds and loads of the engine.


Float Circuit



Fuel in the carburetor must be maintained at a certain level under all operating conditions; this is the function of the float circuit. The needed fuel level is maintained by the float. When its attached lever forces the needle valve closed, the flow of fuel from the pump is stopped. As soon as fuel is discharged from the float bowl, the float drops. The needle valve opens and fuel flows into the bowl again. In this way, the fuel is level to the opening of the main discharge nozzle. The float level must be set with a high degree of accuracy. If the level is too low, not enough fuel will be supplied to the system and the engine will stall on turns; if the level is too high, too much fuel will flow from the nozzle.


Metering Rod



A metering rod varies the size of the carburetor jet opening. Fuel from the float bowl is metered through the jet and the metering rod within it. The fuel is forced from the jet to the nozzle extending into the venturi. As the throttle valve is opened, its linkage raises the metering rod from the jet. The rod has several steps, or tapers, on the lower end. As it is raised in the jet, it makes the opening of the jet greater in size. This allows more fuel to flow through the jet to the discharge nozzle. The metering must keep pace with the slightest change in the throttle valve position so that the correct air-fuel mixture is obtained in spite of engine speed.


Choke Valve



Chokes perform the fuel mixture adjustments necessary to start a cold engine. When the fuel-air mixture is too cold, the engine won't start properly, or will stall out periodically. The choke when engaged (closed) the choke causes the fuel air mixture to be increased, or "enriched". The choke is a special valve placed at the mouth of the carburetor so that it partially blocks off the entering air. When the choke plate closes, the vacuum below it increases, drawing more fuel from the fuel bowl. The rich fuel mixture burns even at lower temperatures, allowing the engine to warm up.

The manual choke is a knob on the dash, usually the push-pull type, which extends from the choke on the carburetor to the instrument panel. The driver closes the choke when starting the engine. The main thing to know about a manual choke is to push it back in when the engine has reached normal operating temperature. The trouble with the manual choke is that the driver often forgets to open it fully. This results in a rich fuel mixture which causes carbon to form in the combustion chambers and on the spark plugs. To correct this problem, the automatic choke was developed.

The automatic choke relies on engine heat. The choke valve is run by a thermostat which is controlled by exhaust heat. When the engine is cold, the valve will be closed for starting. As the engine warms, the exhaust heat will gradually open the choke valve. An automatic choke depends on a thermostatic coil spring unwinding as heat is supplied. As the engine warms up, manifold heat is transmitted to the choke housing. The heat causes the bimetal spring to relax, opening the valve.

An electric heating coil in the automatic choke shortens the length of time that the choke valve is closed. As the spring unwinds, it causes the choke valve in the carburetor air horn to open. This lets more air pass into the carburetor. The coil is mounted in a well in the exhaust crossover passage of the intake manifold. Movement of the bimetal spring is relayed to the choke valve shaft by means of linkage and levers.


Idle Circuit



The fuel delivery in a carburetor tends to lag behind the motion of the throttle. The basic carburetor operates when the throttle valve is fully open or partially open, but not when it's closed. No driver wants the engine to stop every time the foot leaves the accelerator; such a car would be tiring and stressful to drive, even in the best of road conditions, let alone in a traffic situation. To keep the engine running smoothly and evenly when no power is needed, the idle circuit was added inside the carburetor. The idle jet admits fuel on the engine side of the throttle valve. Additional air is mixed with this fuel through an air bleed. The result is an entirely separate carburetor circuit which operates only when the throttle valve is closed.
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Old 01-04-2013, 05:25 PM   #23 (permalink)
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Not sure if you can see this too well, might have to zoom in...tried to figure out a way to get a single page of a large .pdf file to post as a picture.
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Old 02-24-2013, 05:37 PM   #24 (permalink)
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Why do I have fuel in the line here at the choke breaker to vacuum? When I remove the jet it is wet with fuel. Also when the jet is removed and the lines open it runs almost perfect. With the Jet in place or even attached to the vacume line but unattached from the choke breaker it runs really rough and the exhaust smells like raw fuel.
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Old 02-25-2013, 09:23 AM   #25 (permalink)
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Quote:
Originally Posted by tandreas View Post
Why do I have fuel in the line here at the choke breaker to vacuum? When I remove the jet it is wet with fuel. Also when the jet is removed and the lines open it runs almost perfect. With the Jet in place or even attached to the vacume line but unattached from the choke breaker it runs really rough and the exhaust smells like raw fuel.
First thing to look at is the free and easy stuff. If it runs better with a large vacuum leak, then you are clearly getting too much fuel.

Verify your fuel level and make sure that you are not flooding out the bowl.

Verify your fuel inlet, return, and vent lines are hooked up proper.

Verify that you have all of your vacuum lines hooked up proper.
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