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Discussion Starter #1
Looking for the correct measurement for the late stly plastic floats on Weber DCOE 151. As it stands the closet thing to be correct I've found is 12.5 to 13 mm measured at the top of the float when held vertical (See pictures).

If this is correct then great, but what about extended? The only thing I have been able to find says 25 mm, but that does not sound right. Another reference I have says it should extend 6.5 mm, which sounds more reasonable. If this is the case and the 12.5-13 mm measurement is correct, then I should expect a 19-19.5 mm when extended.

Also I attached a some photos of a temp repair I did on my broke float bowl cover. Not sure if it has been tried before, but I suspect it should work until I can get good covers.
 

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Ron, as I do not use the plastic floats, I would suggest you contact Gronway Perry <[email protected]> or try his cell (408) 781-3770. Tell him I sent you.
 

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71 Berlina 74 GTV 17 Giulia Q4
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at the risk of starting a new thread might I ask what you found out? I'm also rebuilding a set of 151's
The float level spec I found from Pierce is 12mm. My question is where do you measure? I've got 12 in the middle including gasket but one end is greater than 12 and the other is less than 12 so I'm assuming:) one would split the diff and measure in the middle of the plastic float.
If I might ask what motor are you running your 151's on? Mine is a 2L with IAP performance cams, head and manifold ported to Jim K's specs, 10:1 motronics, and headers. These carbs came with a spider I found sitting in a shipping container for the last 20 years and were not on the engine. Apparently the PO was going to put them on the car but never did so they've never been run as far as I know.
If yours is also a 2L would you mind sharing your jetting info? Also the 151's seem to have an air compensation needle valve that is not shown on any of the weber breakdowns. Bradon's book shows them on the IDA's but not on the DCOE's. What is a good starting point? They are held with a locknut and I've set mine initially at 1/2 turn out but that is a pure dee guess, poke and hope setting.
here's mine but untested:
mains 130
Air C 200
idle 45 F9
emulsion tubes F9
pump jet 40
main venturi 45
Any input would be greatly appreciated!
 

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Discussion Starter #5
I remember correctly the measurement was 12.5 MM from the bottom, with an extension of 12.5 measured from the same point (not to exceed 25 MM). I got this information from Centerline. As far as the engine it is a 2L and I currnetly have the original type cams. They were repplaced about 10 years ago, but to the best of my knowledge they were replaced by original or aftermarket copies, the same holds true for the rest of the engine. Bening mechanically stupid I could not fathom what my jet settings are for the webers as I have never asked for no attempted to change their settings. If this is indeed correct then my settings are as follows:
mains 115
Air C 200
idle 45 F9
emulsion tubes F11
pump jet 40
main venturi 30
There is indeed an air compensation needle and everything I came across said to not adjust it and to screw it in all the way and lock it in place.

Hopefully this helps. If you have an email I can send you whhat files I have that kind of led me in the a direction, may not be the right direction, but it gace me direction.
 

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71 Berlina 74 GTV 17 Giulia Q4
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I just found out something on my 151's. The spec is 12 mm so I set mine at 12 in the middle, one end was more the other less. Started the car and fuel flooded out the throttle bodies. Took the top off and set them back to where they were when they came out of the box which was parallel to the top and it measured 16mm, in any event they were parallel to the top of the carb. Put them back on and the car runs great. Did have one clogged idle jet on #3 but got that taken care of and the car runs great throughout the throttle range, good at a no load running, great progression to the mains and a fantastic run up to 7000. Hope that helps.
 
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