Weber 40 IDA 3C problem

[targa67]

Hi!

I need help with my Weber 40 IDA 3C, which are running bad

I have opened them up, and will give them a good cleaning (ultrasound) incl. new gaskets, with a kit I bought.
While doing this I noticed that 1 of 6 air corrector jets (#74) is lower than all the others.
The 1st cylinder the head is level with carb. top. (left side, marked in yellow)
Is this normal?
Shall not all have the same hight, and shall they all be level as this 1/6, or shall all be a bit above?
Seems odd that only one is different!
Unscrewed #74 (the level one), and this (#73) emulsion tube sits lower in the carb for 1st cylinder than on the others do.
Either this #73 is correct, and all others sit to high, or something is wrong with this tube, and it sits to low..

Thanks for your input!

/Steffen

[Walt Fricke]

Does seem odd. Are all the emulsion tubes the same? They are marked on the sides. Even if marked the same, are all six dimensionally the same?

Since part of the voodoo of emulsion tubes has to do with where the holes are, a slight mismatch could cause a slightly different mixture.

If the center tube on each side were to be higher, one could conjure up a rationale - in a Porsche the center intake flows better, because there are no bends in the manifold. But Weber didn't design these carbs for Porsche - Porsche just made manifolds to handle the carb.

[targa67]

Pulled all apart now...
All have same no, and measurements:
-air corrector jets #180
-emulsion # F3

However, the on the left side for the 1st cylinder (marked yellow) does sit 2mm lower!
There is a "shelf" inside where the tube rests upon.
Two are 5mm down, and the lower one is 7mm. (measured when the tubes are in place)
Why is this "shelf lower than all the other five?

I donīt get it

Anybody who has a pair who could check if correct if 1st cylinder sits lower, or has the know-how..

[kent olsen]

Contact Paul Abbott at performance oriented.com or 530 520 5816