There are kludgy fixes. You can pipe another pickup point between the
float bowl and the jet holder (the banjo). I saw that done to a
motorcycle carb (amal monobloc) years ago, and the guy claimed it
worked. then again, I always thought he was full of shit. But the most
likely way to get by is raise the float level to the upper edge (or a
little beyond) of spec, and use a bigger float needle and seat. Raise
the fuel pressure a little tiny bit--the things that get the float
chamber filled quicker but still keeps the needle and seat in control of
level.
I generally run the float level high even on Webers, and then set up the
jetting so it's right with that inherently richer starting point. It
reduces the likelihood of fuel starvation. But then you MUST use a fuel
pressure regulator because you are closer to flooding the engine--you
can't live with a 3 to 5 PSI swing. The float has a smaller range of
motion to work through, and therefore has less closing pressure on the
needle when the chamber is overfilled. If fuel pressure is holding the
needle off the seat initially, a low float level means the float may
still be able to shut off the flow as the level rises. The seat pressure
increases as the fuel level rises because more of the float is
submerged. If there's enough room before the fuel starts running out of
overflows or through the jets, then the car will behave semi-ok.
-----Original Message-----
From: Barr, Scott [mailto:sbarr@mccarty-law.com]
Sent: Friday, January 29, 1999 3:12 PM
To: 'Bill Babcock'
Subject: RE: Fuel System Questions
dang.
> -----Original Message-----
> From: Bill Babcock [SMTP:BillB@bnj.com]
> Sent: Friday, January 29, 1999 5:21 PM
> To: Barr, Scott
> Subject: RE: Fuel System Questions
>
> Yup.
>
> -----Original Message-----
> From: Barr, Scott [mailto:sbarr@mccarty-law.com]
> Sent: Friday, January 29, 1999 2:35 PM
> To: 'Bill Babcock'
> Subject: RE: Fuel System Questions
>
>
> SUs would have this same problem, correct?
>
> > -----Original Message-----
> > From: Bill Babcock [SMTP:BillB@bnj.com]
> > Sent: Friday, January 29, 1999 4:38 PM
> > To: Barr, Scott; 'Friends of Triumph' (E-mail)
> > Subject: RE: Fuel System Questions
> >
> > This is a very common problem with certain carburetor designs that
> > have
> > the fuel pickup from one side or the other of the float bowl.
> Raising
> > the float level or increasing the float needle size (where feasible)
> > sometimes helps a little, but the only cure is multiple fuel pickups
> > or
> > a concentric arrangement of fuel reservoir and emulsion tube. One
> > would
> > think that the fuel would not be affected that much, but a cross
> > section
> > of the fuel in the float bowl of a car turning at .5 G would show
> the
> > fuel surface at a 45 degree angle--the float needle is held shut
> while
> > one side of the bowl is dry.
> >
> >
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