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Re: float bowl overflow Q (PROGRESS!)

To: "Dan Neff" <neffster189@yahoo.com>, "Laury, Victor" <LauryV@MTA.NET>
Subject: Re: float bowl overflow Q (PROGRESS!)
From: "datsunmike" <datsunmike@nyc.rr.com>
Date: Tue, 21 Aug 2001 22:09:31 -0400
It's probably fatigued springs.

----- Original Message -----
From: "Dan Neff" <neffster189@yahoo.com>
To: "Laury, Victor" <LauryV@MTA.NET>
Cc: <datsun-roadsters@autox.team.net>
Sent: Tuesday, August 21, 2001 6:47 PM
Subject: Re: float bowl overflow Q (PROGRESS!)


> Thanks all for the pointers. Victor nailed it:
>
> "Laury, Victor" wrote:
> > Dan, swap float bowl tops with someone and see if the problem changes.
>
>
> No muddobbers (say, is that how it's spelled?), so swapped lid assembly
> (thanks to Mike Koken) with a top that had stock needles. Dialed fuel
> regulator (back to) 5 psi, and ... Ta da!!
> Runs like a top! No overflow, no bumps on acceleration, even idle is a
> little smoother!
> Kewl!
>
>   I don't know much about troubleshooting floats and [Gros]jets (other
> than visible cracks or holes in floats, or Grosjet ball cracked and/or
> wedged), so am thinking I'll see if Scott/ZTherapy will take 'em back and
> give 'em an inspection (in case anyone's wondering, I've been VERY happy
> with his carbs and his servicing the sale).
>
> Thanks all!
> Dan Neff    '69 2000
> Colorado Springs, CO
> www.wycroc.org
>
>
> > -----Original Message-----
> > From: Dan Neff [mailto:neffster189@yahoo.com]
> > Sent: Monday, August 20, 2001 1:58 PM
> > To: Roadster Listgroup
> > Subject: float bowl overflow Q
> >
> > I am stumped y'all. Any idea's?
> >
> > Short version:
> >   All of a sudden my (SU) float bowls started overflowing on high speed
> > downhill decelleration (and gagging and sputtering the engine when
resuming
> > cruise). I have Ztherapy carbs, and Scott Bruning hasn't a clue. The
best
> > improvement I've gotten is by putting a fuel line regulator in (with a
> > mechanical fuel pump!!?) -- setting it to 2psi eliminates the problem
about
> > 95% of the time, but am suspicious it might be leaning it out a hair on
> > acceleration (6,000rpm+) - getting intermittent 'bumps' in the
> > acceleration/-
> > power.
> >   I don't think I've fixed The Problem, just found a workaround. Any
idea's
> > what the REAL problem is?
> >    I'm wondering if the Grosjets could be that touchy about fuel
pressure,
> > except I'd still want an explanation as to why they worked fine for 11
> > months!
> >
> > Long version:
> > [When she gets mad about something...]
> >   Back around the end of June (I'd already put over 5,000 trouble-free
miles
> >
> > on it since a valve/cam job, 10,000 miles since Ztherapy carbs), I
seemed to
> >
> > have gotten a bad tank of gas. Sputtering and spitting off and on.
> > Alternator
> > seized 400 miles later.
> >   What's weird is about that time, I swapped my fuel pump into a 1600 to
> > determine if 1600's pump was bad. When I put mine back (and replaced
alt,
> > checked and re-checked connectors), I started having problems with float
> > bowl overflow on low-grade downhill decelleration (usually above 40mph)!
> >   Did plugs, points, rotor, condenser, cap, swapped an old air filter
> > (being unemployed I had to draw the line somewhere), swapped plug wires,
> > fuel filter, checked floats and Grosjets, and checked with Ztherapy.
still
> > having problems.
> >   Last year, my fuel line gas-tank return reed valve was leaking, so I
had
> > put a "T" in and run a straight line with a restrictor in it back to the
> > tank. It's been fine until now.  So when overflow started happening, I
tried
> >
> > running without any gas tank return restrictor (leaned it out too much
on
> > uphill/load). Drilled out restrictor and improved it significantly. Put
an
> > EI distr'r in, with a 12v coil (which eliminated ballast resistor - a
> > suspect
> > at that point). Nada. 'Borrowed' a reed valve to go back to stock.
Problem
> > was worse!
> >   That's when I tried the fuel line regulator. I'm comfortable daily
driving
> >
> > it at this point, but wouldn't want to take it on a road trip.
> >
> > thanks,
> >
> > Dan Neff    '69 2000
> > Colorado Springs, CO
> > www.wycroc.org

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