Idle problem on Weber 30DGS
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  1. #1
    Tadpole
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    Default Idle problem on Weber 30DGS

    Hi,
    I'm new to this forum. My name is Cees [as in nut case], I'm Dutch and living in New Zealand.
    I've been working for a while now on getting a 1973 GS Break roadworthy, including putting a GSA block in with 5-speed. That's a story in itself, but not the topic of this post.

    My focus is now on getting the engine to run OK and I've run into a problem with the idle setting of the Weber 30DGS 25/250 mark W115-50 on my G13-646 block.

    With the idle speed set to 800 rpm I can turn in the idle mixture till fully closed and the engine will still keep running...
    Seemingly smooth, but it will choke on itself if you quickly open the throttle or it will sometimes just stop by itself. Turning the mixture screw from a few turns out till completely in sees the performance marginally improve with every turn, whereas you would expect to reach an optimum after which it quickly deteriorates.

    Could it be getting mixture from somewhere else? Could the mixture screw be leaking? Any suggestion is welcome.
    Ignition has been set to the required 27 degrees @ 3000 rpm. Could be a degree off but i don't think that's critical. Valve clearance is OK.
    This carb is not the original one: that had a hole. I bought this one second hand. It was quite dirty so I cleaned it, put new gaskets on, etc.

    What would help immensely would be a functional description of this carb. I have the exploded view and the workshop instruction how to tune it, but what I'm looking for is a cross-section and description as to how things should flow during the different regimes of idle, acelaration, normal, 2nd stage, etc.
    Thanks,
    Cees.


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    if your french (like your english) is better than mine, you might find
    carburateur <span class=surlignage>Weber</span> 1130 ( 9/250) adaptable sur une 1300? - Forum de la page de la GS
    touches on your topic (i don't know) - but i just want to be the first to welcome and encourage you.
    steven

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    Quote Originally Posted by citrocees View Post
    Hi,
    I'm new to this forum. My name is Cees [as in nut case], I'm Dutch and living in New Zealand.
    I've been working for a while now on getting a 1973 GS Break roadworthy, including putting a GSA block in with 5-speed. That's a story in itself, but not the topic of this post.

    My focus is now on getting the engine to run OK and I've run into a problem with the idle setting of the Weber 30DGS 25/250 mark W115-50 on my G13-646 block.

    With the idle speed set to 800 rpm I can turn in the idle mixture till fully closed and the engine will still keep running...
    Seemingly smooth, but it will choke on itself if you quickly open the throttle or it will sometimes just stop by itself. Turning the mixture screw from a few turns out till completely in sees the performance marginally improve with every turn, whereas you would expect to reach an optimum after which it quickly deteriorates.

    Could it be getting mixture from somewhere else? Could the mixture screw be leaking? Any suggestion is welcome.
    Ignition has been set to the required 27 degrees @ 3000 rpm. Could be a degree off but i don't think that's critical. Valve clearance is OK.
    This carb is not the original one: that had a hole. I bought this one second hand. It was quite dirty so I cleaned it, put new gaskets on, etc.

    What would help immensely would be a functional description of this carb. I have the exploded view and the workshop instruction how to tune it, but what I'm looking for is a cross-section and description as to how things should flow during the different regimes of idle, acelaration, normal, 2nd stage, etc.
    Thanks,
    Cees.
    Cees,

    I gave that unit's diagram a quick look - the idle mixture circuit looks to be connected via the primary throttle stop circuit - not the same as the two barrel units on D's. However given the problem(s) your describing my first and strongest suspicion is that you have a badly leaking needle/seat assembly. This is will allow gas to constantly flow into both the primary and secondary throttles, makes idle adjustment impossible and can also cause the engine to 'die' from excessive richness. A quick way to visually check - with the air supply tube removed - just shine a light into the top of the carb with the engine idling. If you have a problem with the needle/seat you will see a 'wetness' (gas) on top of one or both of the throttle stops.

    Steve

  4. #4
    Tadpole
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    Thanks for the welcome Steven.
    The article seems to be about someone wanting to convert a GS to LPG. The carb version mentioned is different from mine. There are quite a few variations of the 30DGS used on the different GS models.
    Thanks for the link though.
    Cees.

  5. #5
    Tadpole
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    Thanks Steve,

    I had the distance between the float and the carb lid initially set to 6 mm, which made it flood indeed. I then tweaked it to 6.5 to stop the flooding. Also the needle and seat have been renewed as part of the general overhaul. I will do your test nonetheless to make certain. Thanks for that.

    Are you saying you have a diagram of that carb? Would you mind sharing that with me?

    Cheers,
    Cees.

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    Hi Cees,

    I Just did a quick search with Google and found the following:

    Weber Performance Carburettors

    Just click on 30 DGS and you should have the document pop on your computer. Very few GS cars were sold in the US. The ones we do have are mostly private imports.


    Steve

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    Thanks again Steve.

    Funny how help comes from all over the world.
    The diagram on that page shows an exploded view of the very first version of the Weber 30DGS for the very first GS model. There have been quite a few versions of the 30DGS with changes to the functionality. I'm working on the very latest model .
    Beside an exploded view I'm looking for a cross-section showing all the channels inside, or textual description, or anything to help me understand exactly how the idle regime works. Or can you derive this from an exploded view (coz' I can't)?
    For example: why is there a secondairy idle jet and when does it come into action? This is item 31A on that diagram.

    Cheers,
    C.

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    Cees,

    In looking at the diagram more closely I have to revise my thinking. The 30 DGS looks to be a close cousin of the two barrel units used in D's.

    1) It is a mechanical progressive - most likely the secondary throttle starts to open up when the primary is about 1/2 to 2/3rd open

    2) The 'idle circuit' is part of the secondary throttle.

    3) Like the Webers used on D's I would suspect that the clearance setting of the throttle plate for the primary venturi is quite critical for proper operation. Examine carefully the venturi wall for the primary throttle. You will see a series of small drillings. These are the low speed running or progression holes. Gas entering here flows via a passage from the primary's secondary jet (0.40mm). There, typically, should be no more that 0.003 to 0.005" clearance between the edge of the throttle plate and venturi wall. And none of the progression holes should be uncovered. However the slightest movement of the primary throttle should just start to uncover the bottom most progression hole.

    4) Typically with Webers of this design the transition between the secondary and primary jets will occur starting in the 2000 to 2500 rpm range.

    5) The idle circuit is incorporated into the secondary throttle. This means that for all practical purposes its secondary jet (0.40mm) is the 'idle' jet. It is also why the setting of the primary throttle plate is so critical. You do not want any air/gas mixture getting into the intake, at idle, from the primary throttle. Yet at the same time you need to insure that any movement of the accelerator pedal allows gas to start flowing via the primary so there is no lag in acceleration.

    Just because you replaced the needle and seat does not mean they are good . Have seen new ones for the carbs used on D's leak like a fire hose right out of the package.

    Take care,

    Steve

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    Cees,
    Primary idle jet can be accessed from under a screw into the carb body. When removed you will find a push fit jet in the screw.
    When replacing this only push part way into the holder, it will seat itself correctly as you tighten the holder.

    With the idle jet correctly installed the idle mixture adj screw should be OK at approx 2 turns out.

    Initially I had a thought that the push fit idle jet may be missing. Your carb having been bought second hand?

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    Steve, you got me confused.
    See my comments below and this diagram I found.
    Idle problem on Weber 30DGS-weber30dgs.jpg


    1) It is a mechanical progressive - most likely the secondary throttle starts to open up when the primary is about 1/2 to 2/3rd open
    Cees: Yes, mechanical.

    2) The 'idle circuit' is part of the secondary throttle.
    Cees: Do you mean it is fed by the secondary's mixing tube (not sure if that's the word)? It definitely exits in the primary barrel, through the idle mixture screw just under the butterfly valve.

    3) Like the Webers used on D's I would suspect that the clearance setting of the throttle plate for the primary venturi is quite critical for proper operation.
    Cees: Assuming throttle plate and butterfly valve are the same thing: Yes I heard that. I hardly had the butterfly valve open though.

    4) Typically with Webers of this design the transition between the secondary and primary jets will occur starting in the 2000 to 2500 rpm range.
    Cees: Is this describing the moment the secondary butterfly valve opens, as described in your item 1 at halfway opening of the primary butterfly valve?

    5) The idle circuit is incorporated into the secondary throttle.
    Cees: Same question as item 2.

    This means that for all practical purposes its secondary jet (0.40mm) is the 'idle' jet.
    Cees: There are two idle jets. The primary one, which is incorporated in the electromagnetic shut-off valve on the 'primary side' of the carb. See also Wildebeest's post. And the there is the secondary one, located at the same height but on the 'secondary side' of the carb. Why two? The primary, I'm quite sure, leads to the mixture screw as described under item 2. The secondary leads where? And when does it come into play?

    Just because you replaced the needle and seat does not mean they are good .
    Cees: I checked by blowing and it closed off airtight.

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    Wildebeest, interesting point.
    The primary idle jet is part of the electromagnetic shut-off valve, and indeed it's a push-fit. I believe this is also the case for the secondary idle jet.
    Anyway, I pushed them all the way into their holder and then screwed the assembly into the carb housing.
    I will try again with pushing the jets only half-way in before mounting.
    Gee, where would you find this kind of information?!

    C.

  12. #12
    1000+ Posts Ken W's Avatar
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    I'm dealing with recollections from about 20 years ago on GS and CX motors here but this is my thinking. The 'idle' systems on these carbs serve 2 purposes, 1 to allow the engine to suck (using manifold vacuum) in some fuel emulsion below the butterfly at idle via the mixture screw and into the bottom of the primary barrel to keep the car idling, and 2 through some small holes in both barrels located just above the closed position of the butterfly to allow the engine to suck more fuel in as the butterfly starts to open to help keep the engine running on the transition from idle to main jet venturi operation. I think the idle jet system on the second barrel works mainly for purpose 2.

    If the engine still runs with the mixture screw right in, it must be getting fuel from somewhere else and my guess is from one of the intermediate holes just above the butterfly either in barrel 1 or 2. Maybe the butterfly stop on barrel 2 is set too open so it can get fuel from this barrel?

    Cheers,

    Ken W

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    Thanks for the explanation Ken. That does make sense, and I hope the others can confirm that this is the way it is supposed to work.
    Once I know how it's supposed to work I can look at what it's actually doing. So thanks again.
    C.

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    Quote Originally Posted by citrocees View Post
    Thanks for the explanation Ken. That does make sense, and I hope the others can confirm that this is the way it is supposed to work.
    Once I know how it's supposed to work I can look at what it's actually doing. So thanks again.
    C.
    Cees,

    My mistake in looking at the line drawing. On this unit it looks to be the opposite of the Webers used on DS's cars. If the mixture screw is closing/opening a small hole under the primary throttle plate, then that is where the fuel for idle is being added. However that does not necessary mean that the secondary jet on the primary throttle is the supply jet. Look at the inside wall of the venturi on the secondary throttle and see if you see any small drillings just above where the 'home' position of the throttle plate rests. If not then the secondary jet of the secondary throttle is the jet supplying fuel for the idle mixture screws port. And the secondary throttle plate would be the one used to control the amount of air for the idle setting.

    As Ken observed, if you seat the idle mixture screw and the car will still idle you are getting fuel via the progression circuit(s) in the unit. This means you have got excess air getting into the intake manifold via one or both of the carburetor throats when it should not.

    Basically it works like this. At idle the only fuel that the engine should be seeing only wants to be introduced via the idle mixuture screw and air should only be coming from the idle 'speed' screw- typically one of the throttle plates (normally the one where there are no progression holes drilled into the wall of the venturi throat).

    Just off idle the first of several progression holes will start to be uncovered in the primary barrel. The more accelerator pedal is applied the rest of those progression holes will be uncovered providing more fuel for the engine as a function of the increasing air velocity through the primary throttle. At this point most, if not all, of the gas is being metered by the size of that primary throttle's secondary jet screwed into the side of the carb's body. As the next to last and last progression holes get uncovered there will now be sufficient air velocity (vacuum being generated) to start progressively making the transition from the carbs secondary fuel circuit to the the primary fuel circuit. As the happens fuel will start flowing via the main jet via the spray bridge. As the accelerator pedal is depressed further the mechanical linkage will then start to open the secondary throttle plate and fuel will start to issue from its spray bridge.

    Hope this helps and makes some sense of what is going on.

    Steve

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    Quote Originally Posted by Ken W View Post
    I'm dealing with recollections from about 20 years ago on GS and CX motors here but this is my thinking. The 'idle' systems on these carbs serve 2 purposes, 1 to allow the engine to suck (using manifold vacuum) in some fuel emulsion below the butterfly at idle via the mixture screw and into the bottom of the primary barrel to keep the car idling, and 2 through some small holes in both barrels located just above the closed position of the butterfly to allow the engine to suck more fuel in as the butterfly starts to open to help keep the engine running on the transition from idle to main jet venturi operation. I think the idle jet system on the second barrel works mainly for purpose 2.

    If the engine still runs with the mixture screw right in, it must be getting fuel from somewhere else and my guess is from one of the intermediate holes just above the butterfly either in barrel 1 or 2. Maybe the butterfly stop on barrel 2 is set too open so it can get fuel from this barrel?
    Cheers, Ken W
    Hi Cees,
    I am not familiar with this particular carb but have some experience from the past on carbs on European cars. There has been, I think, a bit of confusion with terminology in some of these replies. The ideas are correct but the parts may have been misrepresented. So I will add my piece.

    Ken has if right in principle. And a good description.

    The carbys are two barrel (or throats) which are almost seperate units in one body. The first one which opens is the primary barrel and the second opening one is the secondary. The primary barrel has an idle circuit, a progression(transition) circuit, and then the main circuit. These operate one after the other as the throttle opens and the air flow increases, and they overlap seamlessly as the next comes in. The second barrel opens as determined by the linkage, after the primary is open to some degree, 40-70% perhaps. It does not have an idle circuit but has a progression circuit, then a main circuit. The progression circuit is the little holes in the barrel at the edge of the throttle plate, and the idle jet and air jet. The idle circuit uses the same jet also. There is also an accelerator pump circuit and a full throttle enrichment circuit. The primary barrel should have the progression holes just covered at idle. The idle fuel then only comes from the idle mixture screw and port.

    If the motor will idle with the primary idle setting badly out of adjustment then you must look elsewhere. It is always assumed the carby mechanical settings are correct. You have set the float level, did you allow for the spring loaded needle tip ? Try to reduce the level another 0.5 mm. If it is idling on the secondary throat to some degree it will stumble as the throttle is opened as both of the progression circuits are not operating correctly.

    The second barrel must be shut correctly, so it does not idle on the air from it or use its fuel. If the setting is unknown then check that it is fully shut and almost no gap at any point, 0.003-5" as said. Hold it up to the light and look through. Check the linkage and back off the stop screw, and see it does not hold it open. If necessary loosen the screws holding the throttle plate and shut it fully and then retighten the screws so it centers properly. Adjust the stop screw so it just holds it from jamming as it opens and closes. If necessary disconnect the linkage and just run on the first barrel till it is running correctly. It should run perfectly, with reduced power When reconnecting there should be no addition problems just improved performance.

    Another thing to note is the fact that as pollution became an issue, the idle mixture range of adjustment was restricted to reduce the opportunity for bad adjustment. So the range of rich adjustment was reduced compared to older carbs and the lean end was similar.
    Good luck jaahn
    Last edited by jaahn; 4th March 2014 at 01:17 PM.

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    Thanks Steve,

    What makes it confusing to me is the multiple meanings of the word 'secondary'.
    The way I understand your explanarion now is:
    a. there are the primary and secondary barrels (I'll call them barrel 1 and barrel 2 from here on) barrel 1 is where the mixture screw exits in, it also barrel 1's butterfly valve that's being controlled by the idle speed screw,
    b. there are a primary and secondary idle jet, the primary being part of what I will call the idle circuit including the shut-off valve and mixture screw and the secondary being part of what I will call the progression circuit, feeding the holes that I suspect to be also in barrel 1 as barrel 2 is fully closed and stays closed until halfway opening barrel 1
    C. in your last paragraph you talk about the carb's secondary and primary fuel circuit, by which I think you mean the idle + progression circuit versus the main circuit including the spray bridge.

    Correct?


    Anyway, at this point I should pause the discussion until I had a proper look again at the carburetor to confirm/test all of the above: I haven't had an opportunity to visit the car since we started the discussion as it is stored somehwere else from where I live.

    Thanks for your help to all of you.
    C.

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    Thanks Jaahn,

    I think your explanation largely corresponds with my summary.
    Hopefully more news from me next week.

    Thanks

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    Quote Originally Posted by citrocees View Post
    Thanks Steve,

    What makes it confusing to me is the multiple meanings of the word 'secondary'.
    The way I understand your explanarion now is:
    a. there are the primary and secondary barrels (I'll call them barrel 1 and barrel 2 from here on) barrel 1 is where the mixture screw exits in, it also barrel 1's butterfly valve that's being controlled by the idle speed screw,
    b. there are a primary and secondary idle jet, the primary being part of what I will call the idle circuit including the shut-off valve and mixture screw and the secondary being part of what I will call the progression circuit, feeding the holes that I suspect to be also in barrel 1 as barrel 2 is fully closed and stays closed until halfway opening barrel 1
    C. in your last paragraph you talk about the carb's secondary and primary fuel circuit, by which I think you mean the idle + progression circuit versus the main circuit including the spray bridge.

    Correct?


    Anyway, at this point I should pause the discussion until I had a proper look again at the carburetor to confirm/test all of the above: I haven't had an opportunity to visit the car since we started the discussion as it is stored somehwere else from where I live.

    Thanks for your help to all of you.
    C.

    Hi Cees,

    1) The 'primary' throttle (barrel) is the one that is operated by the accelerator linkage connected to the pedal in the car.

    2) The 'secondary throttle (barrel) in a progressive type carburetor is the one that starts to be opened via a small linkage arm/connection from the 'primary' when it is approx 1/2 way opened.

    3) For the primary throttle (barrel) you will have two jets that control the amount of fuel that pass through them. The primary jet that meters fuel at higher rpm's and the secondary jet for low rpm's. The primary or main jet issues fuel into the carb via the spray bridge (sometimes referred to as a 'secondary venturi - just to make things more confusing) that sits at the top edge of the throttle/barrel opening and is held in place via the top plate of the carb. The secondary jet (sometimes referred to as the 'low speed' jet) issues fuel into the throttle/barrel via a series of small holes in the wall of the throttle/barrel just above the seated or closed position of the butterfly/throttle plate. These holes are normally referred to as the 'progression holes'. Their purpose is to supply fuel for the engine at low vacuum/air speed values - before sufficient vacuum is developed to activate the main or primary fuel circuit in the primary throttle/barrel.

    4) The secondary throttle/barrel - at least in most of the Weber designs I am familiar with - will have a main or primary jet and a secondary jet. The secondary jet is in actual fact the jet used to control fuel flow for the idle circuit as the secondary throttle/barrel has no 'progression holes'. The secondary throttle/barrels throttle plate/butterfly is the one typically used to control the amount of air to adjust idle speed.

    In addition to all of this you will also find in the unit the emulsion tubes and air correction jets. Their purpose is to control not only the emulsification of the fuel with air prior being ejected into the carbs throttle/barrel as the primary fuel circuit is brought into play, but also provide a 'leaning out' function as engine speed increases.

    It is in the balancing of all of these various components that Weber excelled .

    Steve

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    Quote Originally Posted by citrocees View Post
    Hi,
    I'm new to this forum. My name is Cees [as in nut case], I'm Dutch and living in New Zealand.
    I've been working for a while now on getting a 1973 GS Break roadworthy, including putting a GSA block in with 5-speed. That's a story in itself, but not the topic of this post.

    My focus is now on getting the engine to run OK and I've run into a problem with the idle setting of the Weber 30DGS 25/250 mark W115-50 on my G13-646 block.

    With the idle speed set to 800 rpm I can turn in the idle mixture till fully closed and the engine will still keep running...
    Seemingly smooth, but it will choke on itself if you quickly open the throttle or it will sometimes just stop by itself. Turning the mixture screw from a few turns out till completely in sees the performance marginally improve with every turn, whereas you would expect to reach an optimum after which it quickly deteriorates.

    Could it be getting mixture from somewhere else? Could the mixture screw be leaking? Any suggestion is welcome.
    Ignition has been set to the required 27 degrees @ 3000 rpm. Could be a degree off but i don't think that's critical. Valve clearance is OK.
    This carb is not the original one: that had a hole. I bought this one second hand. It was quite dirty so I cleaned it, put new gaskets on, etc.

    What would help immensely would be a functional description of this carb. I have the exploded view and the workshop instruction how to tune it, but what I'm looking for is a cross-section and description as to how things should flow during the different regimes of idle, acelaration, normal, 2nd stage, etc.
    Thanks,
    Cees.

    Here's my bit. Have seen many new needle and seats being blamed for carb flooding and erratic running problems when the actual problem was excessive fuel pressure. Have you checked this, adjust it on the low side if necessary or put a restrictor in the line. Those push in idle screw seats were usually set and sealed at the factory to prevent tampering, and the carbs were designed around a very small working adjustment in this area anyway. They're not your normal idle screw arrangement. Good luck.

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    Quote Originally Posted by citrocees View Post
    Thanks Jaahn,

    I think your explanation largely corresponds with my summary.
    Hopefully more news from me next week.

    Thanks
    Hi Cees
    Yes your summary is largely correct. And yes you probably do need to look at the actual item again.

    I still think Steve has misdescribed some functions, but will not get into a distracting discussion. A good cross-section of the correct carby and description in English would be a BIG bonus

    Do you have this book, Citroen GS 1971-1976, all models 1015, 1222CC, owners workshop manual, by Haynes. I have dug into my stock of manuals and have looked at my copy of this manual. It has some diagrams and pictures of the WEBER carbs. Not very much but I could scan them and send, or publish, or ?

    We had a 1220 GS Break for some years in the 90s. Orange colour. I always thought, and still do think, it was the nicest looking model Citroen made. My wife thought it was just great alround and enjoyed driving "her car". Not sure why we sold it now ??

    cheers jaahn
    Last edited by jaahn; 5th March 2014 at 12:18 PM.

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    4) The secondary throttle/barrel - at least in most of the Weber designs I am familiar with - will have a main or primary jet and a secondary jet. The secondary jet is in actual fact the jet used to control fuel flow for the idle circuit as the secondary throttle/barrel has no 'progression holes'. The secondary throttle/barrels throttle plate/butterfly is the one typically used to control the amount of air to adjust idle speed.

    As mentioned the 2nd barrel does add to the idling circuit, and should not actually be fully closed. There is an adjustment stop under the carb to set this butterfly. The butterfly on the 2nd barrel should be set so that the small idle port on the side of the barrel is exposed by half of its diameter. ie so that you can see half of the hole. If this is set to be open too far you will have the problem of the idle mixture not being able to properly controlled by the idle mixture screw.
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    Quote Originally Posted by alan moore View Post
    4)
    As mentioned the 2nd barrel does add to the idling circuit, and should not actually be fully closed. There is an adjustment stop under the carb to set this butterfly. The butterfly on the 2nd barrel should be set so that the small idle port on the side of the barrel is exposed by half of its diameter. ie so that you can see half of the hole. If this is set to be open too far you will have the problem of the idle mixture not being able to properly controlled by the idle mixture screw.
    Hi Alan
    Yes that makes sense to me. There will always be some air flow so a specified setting is better to aim at. With half a progression hole the fuel is just starting also to balance the air flow.
    The "book" says do not play with the secondary throttle stop on pain of death but that does not help if someone already has done it. I have also had problems on other cars when the wire rod link has been put in reversed and is binding just a little bit open when it should be closed .
    jaahn

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    Try using a vacum guage to set up the carbys', removes all the guesswork.

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    Shanadoo, you just added another suspect. The carb is from a GSA and mounted in a GS. As a consequences, the carb has a return pipe, I have nothing to connect that too. There is no line returning to the tank. I was going to put a nylon T in the hose before the pump and connect it to that, but this hasn't happened yet. Currently that return pipe just has a blocked of piece of hose on it.
    Could it be the pressure build up would be too much for this carb's float valve? That would mean that on a GS carb (w/o the return pipe) the float valve would have to be stronger. In any case: I checked for leakage by cranking the engine with ignition off and i did not see fuel leaking onto the butterfly valve, but I will double-check.

    Working with a vacuum gauge would be new territory for me.

    Alan, so barrel 2 may have something to do with? I need to know for certain. For now, since it has a seal on its adjustment screw I will assume it is OK and focus on barrel 1... also because all documentation that I do have indeed says not to mess with it ("factory set with micrometer precision").

    Jaahn, I do have the Haynes and a bunch of other docs including from Citroen, but nothing seems to have that functional description I'm looking for. Just exploded views and setting procedures.

    Regards,
    Cees.

  25. #25
    1000+ Posts Ken W's Avatar
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    Cees,
    If you can find someone with a Peter Russek Pocketbook GS Maintenance guide, I know it has a description and flow diagrams for carbies in it. Just not sure if it has both Webber and Solex or just one. I used to have one of these but I can't find it at the moment.

    Cheers,

    Ken W

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