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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