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It won't leak from there even IF the body is distorted because the fuel level should NEVER reach the upper gasket level unless-- 1) Float is stuck. 2) Needle and seat are damaged or have debris on the seat. 3) Float is improperly set for rise setting. 4) Most likely, fuel pressure overwhelms float weight.
Just lower fuel pressure to 3# or less and if it still leaks, something is wrong with the float / needle / seat arrangement as set-up. Pretty simple to diagnose.
Of course, my mistake
Pete
 

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Discussion Starter #42
It won't leak from there even IF the body is distorted because the fuel level should NEVER reach the upper gasket level unless-- 1) Float is stuck. 2) Needle and seat are damaged or have debris on the seat. 3) Float is improperly set for rise setting. 4) Most likely, fuel pressure overwhelms float weight.
Just lower fuel pressure to 3# or less and if it still leaks, something is wrong with the float / needle / seat arrangement as set-up. Pretty simple to diagnose.
Of course, my mistake
Pete
At least according to the Giulia shop manual, the setup of the needle valve seat consists solely of making sure the gasket (a copper or fiber washer) between the seat and the carburetor body is 1mm thick. Which appears to be the case. But if my float is now working properly, and the needle appears to be working properly (air flows through it when it's open, and won't flow through it when it's closed) it would seem like the bottom of the needle seat assembly is sitting too high up in the float bowl. Time for another look....
 

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OR YOUR FUEL PRESSURE IS TOO HIGH AND OVERWHELMING THE FLOAT WEIGHT. Lower your fuel pressure.
 

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You have a mechanical fuel pump, so I would keep lowering the fuel pressure as Gordon says until, hopefully, the fuel stops leaking.

It is not pressure that matters, it is flow, to keep enough fuel in the carb bowl so your engine does not lean out when you are reenacting a scene from The Italian Job. We talk about pressure because it is easier to measure.
Pete
 

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Discussion Starter #46
3 psi. Do it !
Yes. I did try 3 psi, and still had fuel appearing at the gasket at 2-3000 rpm, even though the fuel pressure reading remained constant. One caveat though: the only regulator I could find locally was a not super well-made Mr. Gasket brand, which, rather than letting you fine-tune the pressure, gives you half pound increments. The not unsurprising thing with the Mr. Gasket regulator is that the psi settings on the dial did not match the psi shown on the pressure gauge. The pressure readings on the gauge were 1/2 to 1 psi higher than the psi setting on the regulator dial.)

One other possibility is that the opening in the needle seat is too big. They come in different diameters. Curiously, the one that was in the carb when I bought the car, is a 1.5. The one that came with Centerline's rebuild kit was 1.75. I'm assuming that a 1.75 would let more fuel in than a 1.5, so after checking the functionality of the original needle/seat, I've stuck with it. If nothing else, it reduces the number of variables at play. I'm going to try and track down some documentation on the diameter of the needle/seat that was originally specified for the 1300 TI with the C32 PAIA 7.
 

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1.75 is Ok because todays 'fuel' has a lighter specific gravity than the gasoline the system was designed to use. Todays 'fuel' includes soluble gasses not used in gasoline.
The most often used fuel pressure regulator designed for use with these systems is the Filter King regulator / filter pictured below with part number. Easily found on e-bay, it includes a built in gauge for easy adjustment.
1611982

Unless you have some other problem, the combination of mechanical or electric pump and this regulator should show no change in running pressure related to engine speed.
 

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Discussion Starter #48
1.75 is Ok because todays 'fuel' has a lighter specific gravity than the gasoline the system was designed to use. Todays 'fuel' includes soluble gasses not used in gasoline.
The most often used fuel pressure regulator designed for use with these systems is the Filter King regulator / filter pictured below with part number. Easily found on e-bay, it includes a built in gauge for easy adjustment.
View attachment 1611982
Unless you have some other problem, the combination of mechanical or electric pump and this regulator should show no change in running pressure related to engine speed.
Gordon - Thanks for illuminating me on all this. That looks like a clever contraption. Do you have one of these on your car, and if so, how did you mount it?
 

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Alfas with Webers have a FRB 11 FISPA regulator / filter mounted on a bracket welded to the right inner fender well panel, near the front Weber, like this one behind the coil. The FRB 11's need rebuilding for modern fuel, so those cars without a rebuilt FISPA unit are well served by the Filter king unit that has greater pressure adjustability, and fuel-proof components. It too can be mounted on a piece of angle bent sheet metal simply screwed to the inner fender well with easy access to the fuel line from the tank and carburetor. It's possible some Alfa's came with a non-welded in bracket, or Ferrari or some other vehicle using the FISPA FRB 11, as a few have arrived in my shop for rebuilding with a sheet metal angle bracket attached.
1611988
 

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Discussion Starter #50
Alfas with Webers have a FRB 11 FISPA regulator / filter mounted on a bracket welded to the right inner fender well panel, near the front Weber, like this one behind the coil. The FRB 11's need rebuilding for modern fuel, so those cars without a rebuilt FISPA unit are well served by the Filter king unit that has greater pressure adjustability, and fuel-proof components. It too can be mounted on a piece of angle bent sheet metal simply screwed to the inner fender well with easy access to the fuel line from the tank and carburetor. It's possible some Alfa's came with a non-welded in bracket, or Ferrari or some other vehicle using the FISPA FRB 11, as a few have arrived in my shop for rebuilding with a sheet metal angle bracket attached. View attachment 1611988
Wow, thank you, Gordon. That is brilliant and super helpful.

Cheers!
 

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Relatively cheap and easy fix for Alfas fuel pressure issues that works.
 

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Consider the Filter King FPR with an aluminum bowl. I bought the 67 mm version with a plastic bowl last August. It became a leaker two weeks after installation at normal engine compartment temperatures. After several failed attempts to stop the leak, bought an aluminum bowl from Eurocarb. No leaks for four months.
 

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Consider the Filter King FPR with an aluminum bowl. I bought the 67 mm version with a plastic bowl last August. It became a leaker two weeks after installation at normal engine compartment temperatures. After several failed attempts to stop the leak, bought an aluminum bowl from Eurocarb. No leaks for four months.
Dang, I thought it was just me. Same thing: plastic bowl Filter King started SPRAYING fuel in under one month. I now have a glass bowl one that has been working okay.
 

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Apparently the glass and metal bowls work fine. Although, alfaparticle (Ed Prytherch) has reported the larger version with a plastic bowl has been trouble free on his Spider for at least a few years.
 

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lthough, alfaparticle (Ed Prytherch) has reported the larger version with a plastic bowl has been trouble free on his Spider for at least a few years.
Since September 2016
 

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I hope we have tried turning the pressure down to almost 0 to see what happens re leak, as a test.

If close to no pressure and still leaks we are barking up the wrong tree ...
Pete
 
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