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Gordon told me that he ordered always the longest version, wich he cutted to the same length as the old one, so maybe its a hint
You think that there is only one length available any more so that might be the only option? Since Weber closed shop and the production moved to the newer company, that might be all that you can do. At least we have come to some sort of a conclusion, but not totally resolved. I will be checking my friends Weber carb this afternoon and will report back.
 

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I am not sure about the answer to this issue with your carburetor other than to say that the length of rod you have was identical to what I found in two 40DCOE38 carburetors. The length was 66 mm. So, I am at a loss to explain your situation.
 

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Discussion Starter · #43 ·
Could you also measure the length of travel of the pump rod from fully closed to fully open? It seems that's the only variable remaining which could be different between them.

I'm at a loss myself although that is less surprising considering my lack of experience working with this carburettor.
 

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Next question, what do you know about the history of these carbs? I am wondering if you have the wrong accelerator pump installed? What is the measured length of the pump rod?

An odd thing could have happened, that the pump cam on the rod has slipped putting the butterflies out of synch with the pump rod. Is the pin in place that it goes all the way through the throttle shaft?
It's highly unlikely that the pump cam has 'slipped'. You can see the roll pin holding it in place. If you make a mess of removing it ( it requires a 2mm punch - an old drill for instance, using the NON drill end) by causing it to jam in the hole, then you are into cutting the lever off and possibly ruining the throttle shaft.
 

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Discussion Starter · #45 ·
Quick update, I measured the length of travel of my carburettors' accelerator pump to be 15.4mm. I'm interested to know whether there is a standard length or this could be adjusted to relieve force on the throttle rod.

It's highly unlikely that the pump cam has 'slipped'. You can see the roll pin holding it in place. If you make a mess of removing it ( it requires a 2mm punch - an old drill for instance, using the NON drill end) by causing it to jam in the hole, then you are into cutting the lever off and possibly ruining the throttle shaft.
I agree, I believe the issue to be either the return spring, accelerator pump spring, or accelerator pump length.
 

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Hi Jarred,
I started reading this as a moderator as most threads are followed. This one has plenty of BB helpers with experience offering suggestions. First, Richard's comments on correct curve for the distributor, is correct and critical to proper function.
I have not seen enough photos of the balance link assembly, but know the alterations are odd, and will lead you to many problems. There are TWO basic types of balance links between Webers, and the old style and current style have different centers of rotation, and you cannot use the new paddle link with the old "U" link and vice versa. BOTH halves muct come from the same version of the link. I'll try to post photos of both styles below.
Rather than comment on all the issues others have discussed, I would be happy to help you out if you send me a PM with your e-mail address. In that way I can ask critical questions, and cut-to-the-chase. To run through every issue that might be required to make your Webers function correctly on your engine could run into a short book! We don't want to do that here, as I've too many jobs waiting.
Photo 1 is a pair of older Italian Webers with the original style balance linkage. Photo 2 is that same style linkage from another pair of Webers. Photo 3 is the NEW style linkage (heavier with longer center of rotation) on a restored set of race Webers. Do NOT mix and match these two balance link styles!
 

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Discussion Starter · #47 ·
Thanks, Gordon. I definitely have both sides of the newer style linkage. Also, PM sent. I've lost the eclip that connects the original spring - I'll source another one and can try returning it to original state.
 

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The clip is metric, but the USA inch one fits fine, as it's just a bit tight. Guess how I learned that? (hint... ping!!!)
 

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As a word to the wise, Weber restoration and R & R of plates, bar, cam and bearing is not a DIY proposition unless you do it often, and even then, it's very easy to lose "balance" between the two throats in any body. Also, Spanish Webers ultrasonic clean fine, but older Italian Webers frequently suffer damage from "leaking" brass inserts. It usually difficult to find the leaker, and correction is another issue in itself. I do not use ultrasonic cleaning on Italian made Webers.
Gas Motor vehicle Engineering Machine Auto part
 

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Where RJ?
Gas Machine Engineering Table Space
 

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Richard Jemison
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Where did my pics go :unsure:
Your`s are baby carbs for Mouse motors.

Motor vehicle Gas Machine tool Engineering Machine

50s on the new race engine that isn`t going into the GTAm. Holes are 55mm
Gas Machine Auto part Metal Motor vehicle

The ones going on the race motor that is going into the GTAm.
 

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I don't have a picture, but Ferrari used HUGE DCO3's on the 625 4 cylinder Monza engines. These are >smaller< versions on my 2L Ferrari 500TRC #702. I bought and sold it twice. Probably should have kept it. Note my Ausca Alfa in the background. I did keep that.
Hood Motor vehicle Vehicle door Tints and shades Automotive design
Tire Wheel Land vehicle Car Vehicle

Mouse motor Ferrari.
 
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