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Carburetor questions

Old 11-03-2011, 10:11 AM
  #41  
Ganey
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Yes, one of several methods used to operate the choke.
Old 11-03-2011, 03:43 PM
  #42  
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Default Is it the "divorced choke"? what is its purpose?

Let me elaborate a bit. The choke coil (bimetallic) is inside that rectangular housing on the intake manifold. That is why it is called divorced - it is not integral with the carb itself. The bimetallic moves that vertical rod in your photo.
The linkage is attached to the choke rod which passes through the carb body into the well (the trangular opening you see) and operates the vertical rod that is attached to the choke plate. If that rod comes off inside the well, manually rotate the linkage so the arm inside the well it at the widest part of the well and hook it back on.
Hope this helps.
Old 11-04-2011, 04:23 AM
  #43  
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Originally Posted by Rich's'78
Let me elaborate a bit. The choke coil (bimetallic) is inside that rectangular housing on the intake manifold. That is why it is called divorced - it is not integral with the carb itself. The bimetallic moves that vertical rod in your photo.
The linkage is attached to the choke rod which passes through the carb body into the well (the trangular opening you see) and operates the vertical rod that is attached to the choke plate. If that rod comes off inside the well, manually rotate the linkage so the arm inside the well it at the widest part of the well and hook it back on.
Hope this helps.
Thank you I'm starting to understand better! Do I have to do some maintennace inside the divorced choke or I just remove the carb??
Old 11-04-2011, 01:47 PM
  #44  
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Just remove the carb. Leave the lever attached to the choke coil attached to the coil. Don't lose the attaching clip.
Old 11-04-2011, 01:57 PM
  #45  
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Originally Posted by Rich's'78
Just remove the carb. Leave the lever attached to the choke coil attached to the coil. Don't lose the attaching clip.
Thank you!
Old 11-10-2011, 07:54 AM
  #46  
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Originally Posted by Rich's'78
Let me elaborate a bit. The choke coil (bimetallic) is inside that rectangular housing on the intake manifold. That is why it is called divorced - it is not integral with the carb itself. The bimetallic moves that vertical rod in your photo.
The linkage is attached to the choke rod which passes through the carb body into the well (the trangular opening you see) and operates the vertical rod that is attached to the choke plate. If that rod comes off inside the well, manually rotate the linkage so the arm inside the well it at the widest part of the well and hook it back on.
Hope this helps.
I've understood that the purpose of this choke is to allow a richer mix for cold start. This choke closes the smaller butterfly on the top of the QJet (not completely, it remains open only for a small quantity of air) and then, when the motor starts to warm up, they open slowly. I've noticed mine is always open so the next question is: can I do something to fix it? Thanks

Last edited by Iron_dog; 11-11-2011 at 03:36 AM.
Old 11-10-2011, 01:14 PM
  #47  
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I don't remember bending which linkage arm is the proper way to adjust it. The choke plate should be fully closed when cold and not running. The engine vacuum to the 'choke pull-off' should crack the choke plate open when it starts. The bimetallic should gradually open the choke plate as it warms up.
I'm sure someone here has the correct numbers for a '74's adjustments.
Old 11-25-2011, 06:00 AM
  #48  
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Guys, in this weekend I will start to clean the carburator.
One question: removing it from the motor, I've noticed there's a part of the linkage that has a hole with nothing attached. Is it OK or I'm missing something??? Please look at the picture attached.

Old 11-25-2011, 04:19 PM
  #49  
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I don't know and I am unsure, but my best guess is there should be a rod for the "Unloader" function. If you flood the engine when warm, the unloader overcomes the choke operation (floor the gas pedal and hold it down, forces the choke plate to open, against the bimetallic's will) so as to let more air in and clear the flooded condition.
Your rebuild kit should have a diagram and instructions for adjusting the unloader.
Your best bet may be to email the photo to Cliff Ruggles and ask. If you never experience warm/hot re-start problems, you probably don't need it.
Best advice I can give is never touch the gas pedal on a warm start, let it crank 2 - 3 seconds and then lightly touch the gas.
BTW, if you flood the sucker, pop the hood and insert a LARGE-handled screwdriver to hold the choke plate open. Crank and it should clear right out.

Last edited by Rich's'78; 11-25-2011 at 04:24 PM.
Old 11-26-2011, 11:36 AM
  #50  
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Does anybody knows what is the thing pointed? I've found inside the rebuild kit but I don't understand what is that for....

Old 12-06-2011, 05:42 AM
  #51  
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Guys, I know maybe this is a "stupid" question, but when it comes to adjust idle screws and it's written to count turn, is a turn a 180° rotation or a 360° rotation of the screw???
Old 12-06-2011, 06:45 AM
  #52  
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Iron dog I am also in Italy I am stationed in Sicily. It is usaly a 360 rotation although it depends on who wrote it. If you are on or near the island I dont mind lending a hand depending on how far the travel is.

Andrew
Old 12-06-2011, 07:20 AM
  #53  
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Originally Posted by cm2dinger
Iron dog I am also in Italy I am stationed in Sicily. It is usaly a 360 rotation although it depends on who wrote it. If you are on or near the island I dont mind lending a hand depending on how far the travel is.

Andrew
Andrew, thank you very much for your availability but I live in Milan, it's a bit too far from you! I'm looking for a vacuum gauge in order to do the stuff correctly and I've a doubt on the "turn" word...
Old 12-06-2011, 09:07 AM
  #54  
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I'm not sure who sells inexpencive tools over here but I havent had trouble with harbor fright tools for the seldom used stuff.
Old 12-06-2011, 10:01 AM
  #55  
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Originally Posted by Iron_dog
Does anybody knows what is the thing pointed? I've found inside the rebuild kit but I don't understand what is that for....

That is the seal used for the "Integral" choke housing, not used on your carb. The part pointed to in the pic above this one is the fast idle cam.
Stan.
Old 12-07-2011, 05:28 AM
  #56  
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Ok guys, I've reassembled and cleaned the carb, I've fixed divorced choke stuff, now the car runs even if cold BUT I still have the same problems when I accelerate... The car is not smooth at all!!!! What can I check? Is the accelerator pump, that I have replaced, the problem? Maybe the power piston???
Old 12-07-2011, 02:23 PM
  #57  
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Originally Posted by Iron_dog
Maybe the power piston???
When you had the carb apart, did you remove the power piston from its bore to clean in there?
Did you check to make sure that it was moving freely before you finished putting the carb back together?
If the power piston gets stuck in the down position, you will get a bad lean bog when you try to accelerate.
I used to see that happen quite a bit back when carbs were still common.
Also, if you didnt put the top gasket back on correctly, it can affect the operation of the piston as well.

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Old 12-08-2011, 01:01 AM
  #58  
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Maybe now would be a good time to check your ignition system as was suggested at the beginning of this thread.
Old 12-08-2011, 08:16 AM
  #59  
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Originally Posted by DRIVESHAFT
When you had the carb apart, did you remove the power piston from its bore to clean in there?
Did you check to make sure that it was moving freely before you finished putting the carb back together?
If the power piston gets stuck in the down position, you will get a bad lean bog when you try to accelerate.
I used to see that happen quite a bit back when carbs were still common.
Also, if you didnt put the top gasket back on correctly, it can affect the operation of the piston as well.
Yes I checked the power piston and it was free to move with the gasket installed so I suppose it was installed correctly. I've read somewhere that it's possible to che its functioning when the carb is installed using a straw...
Old 12-08-2011, 08:18 AM
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Originally Posted by sly vette
Maybe now would be a good time to check your ignition system as was suggested at the beginning of this thread.
You are right and I'm going to do it but I also wanted to be sure the carb is OK!

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